diff --git a/package-lock.json b/package-lock.json
index b933ac8..e3da2e9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -21,11 +21,35 @@
         "regenerator-runtime": "^0.12.0"
       }
     },
+    "@types/bn.js": {
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+      "resolved": "https://registry.npmjs.org/@types/bn.js/-/bn.js-4.11.6.tgz",
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+      "requires": {
+        "@types/node": "*"
+      }
+    },
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       "version": "10.14.1",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-10.14.1.tgz",
       "integrity": "sha512-Rymt08vh1GaW4vYB6QP61/5m/CFLGnFZP++bJpWbiNxceNa6RBipDmb413jvtSf/R1gg5a/jQVl2jY4XVRscEA=="
     },
+    "@types/pbkdf2": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/@types/pbkdf2/-/pbkdf2-3.0.0.tgz",
+      "integrity": "sha512-6J6MHaAlBJC/eVMy9jOwj9oHaprfutukfW/Dyt0NEnpQ/6HN6YQrpvLwzWdWDeWZIdenjGHlbYDzyEODO5Z+2Q==",
+      "requires": {
+        "@types/node": "*"
+      }
+    },
+    "@types/secp256k1": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/@types/secp256k1/-/secp256k1-4.0.1.tgz",
+      "integrity": "sha512-+ZjSA8ELlOp8SlKi0YLB2tz9d5iPNEmOBd+8Rz21wTMdaXQIa9b6TEnD6l5qKOCypE7FSyPyck12qZJxSDNoog==",
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@webassemblyjs/ast": {
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       "resolved": "https://registry.npmjs.org/@webassemblyjs/ast/-/ast-1.8.5.tgz",
@@ -1148,6 +1172,14 @@
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+    "base-x": {
+      "version": "3.0.8",
+      "resolved": "https://registry.npmjs.org/base-x/-/base-x-3.0.8.tgz",
+      "integrity": "sha512-Rl/1AWP4J/zRrk54hhlxH4drNxPJXYUaKffODVI53/dAsV4t9fBxyxYKAVPU1XBHxYwOWP9h9H0hM2MVw4YfJA==",
+      "requires": {
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+      }
+    },
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       "resolved": "https://registry.npmjs.org/base64-js/-/base64-js-1.3.0.tgz",
@@ -1206,6 +1238,11 @@
         "safe-buffer": "^5.0.1"
       }
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+    "blakejs": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/blakejs/-/blakejs-1.1.0.tgz",
+      "integrity": "sha1-ad+S75U6qIylGjLfarHFShVfx6U="
+    },
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       "resolved": "https://registry.npmjs.org/bluebird/-/bluebird-3.5.3.tgz",
@@ -1378,6 +1415,24 @@
         "electron-to-chromium": "^1.3.47"
       }
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+    "bs58": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/bs58/-/bs58-4.0.1.tgz",
+      "integrity": "sha1-vhYedsNU9veIrkBx9j806MTwpCo=",
+      "requires": {
+        "base-x": "^3.0.2"
+      }
+    },
+    "bs58check": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/bs58check/-/bs58check-2.1.2.tgz",
+      "integrity": "sha512-0TS1jicxdU09dwJMNZtVAfzPi6Q6QeN0pM1Fkzrjn+XYHvzMKPU3pHVpva+769iNVSfIYWf7LJ6WR+BuuMf8cA==",
+      "requires": {
+        "bs58": "^4.0.0",
+        "create-hash": "^1.1.0",
+        "safe-buffer": "^5.1.2"
+      }
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       "resolved": "https://registry.npmjs.org/buffer/-/buffer-4.9.1.tgz",
@@ -1540,6 +1595,18 @@
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         "websocket": "git://github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2",
         "xhr2-cookies": "^1.1.0"
+      },
+      "dependencies": {
+        "websocket": {
+          "version": "git://github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2",
+          "from": "git://github.com/frozeman/WebSocket-Node.git#browserifyCompatible",
+          "requires": {
+            "debug": "^2.2.0",
+            "nan": "^2.3.3",
+            "typedarray-to-buffer": "^3.1.2",
+            "yaeti": "^0.0.6"
+          }
+        }
       }
     },
     "chai": {
@@ -1848,6 +1915,16 @@
             "websocket": "git://github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2",
             "xhr2-cookies": "^1.1.0"
           }
+        },
+        "websocket": {
+          "version": "git://github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2",
+          "from": "git://github.com/frozeman/WebSocket-Node.git#browserifyCompatible",
+          "requires": {
+            "debug": "^2.2.0",
+            "nan": "^2.3.3",
+            "typedarray-to-buffer": "^3.1.2",
+            "yaeti": "^0.0.6"
+          }
         }
       }
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@@ -2815,6 +2892,59 @@
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         "ethereumjs-util": "^5.1.1"
+      },
+      "dependencies": {
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+          "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.11.9.tgz",
+          "integrity": "sha512-E6QoYqCKZfgatHTdHzs1RRKP7ip4vvm+EyRUeE2RF0NblwVvb0p6jSVeNTOFxPn26QXN2o6SMfNxKp6kU8zQaw=="
+        },
+        "elliptic": {
+          "version": "6.5.3",
+          "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.3.tgz",
+          "integrity": "sha512-IMqzv5wNQf+E6aHeIqATs0tOLeOTwj1QKbRcS3jBbYkl5oLAserA8yJTT7/VyHUYG91PRmPyeQDObKLPpeS4dw==",
+          "requires": {
+            "bn.js": "^4.4.0",
+            "brorand": "^1.0.1",
+            "hash.js": "^1.0.0",
+            "hmac-drbg": "^1.0.0",
+            "inherits": "^2.0.1",
+            "minimalistic-assert": "^1.0.0",
+            "minimalistic-crypto-utils": "^1.0.0"
+          }
+        },
+        "ethereumjs-abi": {
+          "version": "git+https://github.com/ethereumjs/ethereumjs-abi.git#572d4bafe08a8a231137e1f9daeb0f8a23f197d2",
+          "from": "git+https://github.com/ethereumjs/ethereumjs-abi.git",
+          "requires": {
+            "bn.js": "^4.11.8",
+            "ethereumjs-util": "^6.0.0"
+          },
+          "dependencies": {
+            "ethereumjs-util": {
+              "version": "6.2.1",
+              "resolved": "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-6.2.1.tgz",
+              "integrity": "sha512-W2Ktez4L01Vexijrm5EB6w7dg4n/TgpoYU4avuT5T3Vmnw/eCRtiBrJfQYS/DCSvDIOLn2k57GcHdeBcgVxAqw==",
+              "requires": {
+                "@types/bn.js": "^4.11.3",
+                "bn.js": "^4.11.0",
+                "create-hash": "^1.1.2",
+                "elliptic": "^6.5.2",
+                "ethereum-cryptography": "^0.1.3",
+                "ethjs-util": "0.1.6",
+                "rlp": "^2.2.3"
+              }
+            }
+          }
+        },
+        "rlp": {
+          "version": "2.2.6",
+          "resolved": "https://registry.npmjs.org/rlp/-/rlp-2.2.6.tgz",
+          "integrity": "sha512-HAfAmL6SDYNWPUOJNrM500x4Thn4PZsEy5pijPh40U9WfNk0z15hUYzO9xVIMAdIHdFtD8CBDHd75Td1g36Mjg==",
+          "requires": {
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+          }
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@@ -2822,32 +2952,70 @@
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-      "requires": {
-        "bn.js": "^4.11.8",
-        "ethereumjs-util": "^6.0.0"
+    "ethereum-cryptography": {
+      "version": "0.1.3",
+      "resolved": "https://registry.npmjs.org/ethereum-cryptography/-/ethereum-cryptography-0.1.3.tgz",
+      "integrity": "sha512-w8/4x1SGGzc+tO97TASLja6SLd3fRIK2tLVcV2Gx4IB21hE19atll5Cq9o3d0ZmAYC/8aw0ipieTSiekAea4SQ==",
+      "requires": {
+        "@types/pbkdf2": "^3.0.0",
+        "@types/secp256k1": "^4.0.1",
+        "blakejs": "^1.1.0",
+        "browserify-aes": "^1.2.0",
+        "bs58check": "^2.1.2",
+        "create-hash": "^1.2.0",
+        "create-hmac": "^1.1.7",
+        "hash.js": "^1.1.7",
+        "keccak": "^3.0.0",
+        "pbkdf2": "^3.0.17",
+        "randombytes": "^2.1.0",
+        "safe-buffer": "^5.1.2",
+        "scrypt-js": "^3.0.0",
+        "secp256k1": "^4.0.1",
+        "setimmediate": "^1.0.5"
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-          "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.11.8.tgz",
-          "integrity": "sha512-ItfYfPLkWHUjckQCk8xC+LwxgK8NYcXywGigJgSwOP8Y2iyWT4f2vsZnoOXTTbo+o5yXmIUJ4gn5538SO5S3gA=="
+        "elliptic": {
+          "version": "6.5.3",
+          "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.3.tgz",
+          "integrity": "sha512-IMqzv5wNQf+E6aHeIqATs0tOLeOTwj1QKbRcS3jBbYkl5oLAserA8yJTT7/VyHUYG91PRmPyeQDObKLPpeS4dw==",
+          "requires": {
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+            "brorand": "^1.0.1",
+            "hash.js": "^1.0.0",
+            "hmac-drbg": "^1.0.0",
+            "inherits": "^2.0.1",
+            "minimalistic-assert": "^1.0.0",
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+        "keccak": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/keccak/-/keccak-3.0.0.tgz",
+          "integrity": "sha512-/4h4FIfFEpTEuySXi/nVFM5rqSKPnnhI7cL4K3MFSwoI3VyM7AhPSq3SsysARtnEBEeIKMBUWD8cTh9nHE8AkA==",
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-            "keccak": "^1.0.2",
-            "rlp": "^2.0.0",
-            "safe-buffer": "^5.1.1",
-            "secp256k1": "^3.0.1"
+            "node-addon-api": "^2.0.0",
+            "node-gyp-build": "^4.2.0"
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+        "scrypt-js": {
+          "version": "3.0.1",
+          "resolved": "https://registry.npmjs.org/scrypt-js/-/scrypt-js-3.0.1.tgz",
+          "integrity": "sha512-cdwTTnqPu0Hyvf5in5asVdZocVDTNRmR7XEcJuIzMjJeSHybHl7vpB66AzwTaIg6CLSbtjcxc8fqcySfnTkccA=="
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+        "secp256k1": {
+          "version": "4.0.1",
+          "resolved": "https://registry.npmjs.org/secp256k1/-/secp256k1-4.0.1.tgz",
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+          "resolved": "https://registry.npmjs.org/setimmediate/-/setimmediate-1.0.5.tgz",
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@@ -2926,6 +3094,14 @@
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       },
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+          "version": "0.2.4",
+          "resolved": "https://registry.npmjs.org/async-eventemitter/-/async-eventemitter-0.2.4.tgz",
+          "integrity": "sha512-pd20BwL7Yt1zwDFy+8MX8F1+WCT8aQeKj0kQnTrH9WaeRETlRamVhD0JtRPmrV4GfOJ2F9CvdQkZeZhnh2TuHw==",
+          "requires": {
+            "async": "^2.4.0"
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@@ -3602,7 +3778,8 @@
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-          "dev": true
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@@ -3623,12 +3800,14 @@
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           "version": "1.0.0",
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-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.1.11",
           "bundled": true,
           "dev": true,
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@@ -3643,17 +3822,20 @@
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           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
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@@ -3770,7 +3952,8 @@
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-          "dev": true
+          "dev": true,
+          "optional": true
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@@ -3782,6 +3965,7 @@
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           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3796,6 +3980,7 @@
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           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3803,12 +3988,14 @@
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           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "bundled": true,
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@@ -3827,6 +4014,7 @@
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@@ -3907,7 +4095,8 @@
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@@ -3919,6 +4108,7 @@
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@@ -4004,7 +4194,8 @@
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@@ -4040,6 +4231,7 @@
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           "bundled": true,
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@@ -4059,6 +4251,7 @@
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@@ -4102,12 +4295,14 @@
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           "version": "1.0.2",
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-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "3.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
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@@ -5361,9 +5556,9 @@
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-      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz",
-      "integrity": "sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg=="
+      "version": "4.17.19",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.19.tgz",
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       "dev": true
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+    "node-addon-api": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/node-addon-api/-/node-addon-api-2.0.2.tgz",
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+    },
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@@ -5790,6 +5990,11 @@
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       "dev": true
     },
+    "node-gyp-build": {
+      "version": "4.2.2",
+      "resolved": "https://registry.npmjs.org/node-gyp-build/-/node-gyp-build-4.2.2.tgz",
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+    },
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@@ -8969,16 +9174,6 @@
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-    "websocket": {
-      "version": "git://github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2",
-      "from": "git://github.com/frozeman/WebSocket-Node.git#browserifyCompatible",
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