Upgrade IcedFrisby (#1360)

IcedFrisby/IcedFrisby#71 will allow us to set a per-test `timeout()` and per-test `retry()`, which should allow us to keep flaky tests green most of the time.

A slough of service tests are failing locally, though they are also failing in master and seem unrelated to these changes. (#1359)

IcedFrisby is maturing toward a 2.0 API. There's been one breaking change to the way dependencies are installed, and probably more changes to come in the API itself. Shields uses such a small part of that API that 2.0, when it's released, may not even affect us.

package.json

@@ -111,10 +111,11 @@
     "eslint-plugin-standard": "^3.0.1",
     "fetch-ponyfill": "^4.1.0",
     "glob": "^7.1.1",
-    "icedfrisby": "^1.4.0",
+    "icedfrisby": "2.0.0-alpha.1",
     "icedfrisby-nock": "^1.0.0",
     "is-png": "^1.1.0",
     "is-svg": "^2.1.0",
+    "joi": "^12.0.0",
     "lodash.debounce": "^4.0.8",
     "lodash.difference": "^4.5.0",
     "lodash.mapvalues": "^4.6.0",