Document contract_templates

packages/contract_templates/README.md

@@ -0,0 +1,15 @@
+These templates are used with [abi-gen](https://github.com/0xProject/0x-monorepo/tree/development/packages/abi-gen).
+
+To successfully compile the generated TypeScript contract wrappers, you must:
+* Install the packages on which the main contract template directly depends: `yarn add @0xproject/base-contract @0xproject/sol-compiler @0xproject/types @0xproject/utils @0xproject/web3-wrapper ethers lodash`
+* Install the packages on which the main contract template *in*directly depends: `yarn add @types/lodash`
+* Ensure that your TypeScript configuration includes the following:
+```
+"compilerOptions": {
+  "lib": ["ES2015"],
+  "typeRoots": [
+    "node_modules/@0xproject/typescript-typings/types",
+    "node_modules/@types"
+  ]
+}
+```