Merge branch 'development' into v2-prototype

* development: (29 commits)
  Do not remove artifacts when running `clean`
  fix style errors
  Fix circular dependency
  Add my profile image to images
  Add myself to about page
  Add dogfood configs to website
  Revert to lerna:run lint
  Do lint sequentially
  Exclude monorepo-scripts from tslint as test
  Fix prettier
  Add hover state to top tokens
  Change to weekly txn volume
  Change minimum Node version to 6.12
  Document Node.js version requirement and add it to package.json
  Apply prettier to some files which were not formatted correctly
  Fix TSLint issues
  Fix TSLint issues
  Update ethereeumjs-testrpc to ganache-cli
  Fix infinite loop
  Add changelog entries for packages where executable binary exporting fixed
  ...

# Conflicts:
#	packages/contracts/package.json
#	packages/contracts/util/formatters.ts
#	packages/contracts/util/signed_order_utils.ts
#	packages/migrations/package.json
#	yarn.lock

6 files changed, 19 insertions, 30 deletions

diff --git a/packages/contracts/README.md b/packages/contracts/README.md
index 16e253549..23551b69d 100644
--- a/packages/contracts/README.md
+++ b/packages/contracts/README.md
@@ -34,28 +34,16 @@ yarn install
 
 ### Build
 
-If this is your **first** time building this package, you must first build **all** packages within the monorepo. This is because packages that depend on other packages located inside this monorepo are symlinked when run from **within** the monorepo. This allows you to make changes across multiple packages without first publishing dependent packages to NPM. To build all packages, run the following from the monorepo root directory:
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
 
 ```bash
-yarn lerna:rebuild
+PKG=contracts yarn build
 ```
 
 Or continuously rebuild on change:
 
 ```bash
-yarn dev
-```
-
-You can also build this specific package by running the following from within its directory:
-
-```bash
-yarn build
-```
-
-or continuously rebuild on change:
-
-```bash
-yarn build:watch
+PKG=contracts yarn watch
 ```
 
 ### Clean
diff --git a/packages/contracts/package.json b/packages/contracts/package.json
index 11db3880a..b10ed3c44 100644
--- a/packages/contracts/package.json
+++ b/packages/contracts/package.json
@@ -2,25 +2,25 @@
     "private": true,
     "name": "contracts",
     "version": "2.1.28",
+    "engines": {
+        "node" : ">=6.12"
+    },
     "description": "Smart contract components of 0x protocol",
     "main": "index.js",
     "directories": {
         "test": "test"
     },
     "scripts": {
-        "build:watch": "tsc -w",
+        "watch": "tsc -w",
         "prebuild": "run-s clean copy_artifacts generate_contract_wrappers",
         "copy_artifacts": "copyfiles -u 4 '../migrations/artifacts/2.0.0/**/*' ./lib/src/artifacts;",
         "build": "tsc",
         "test": "run-s build run_mocha",
         "test:coverage": "SOLIDITY_COVERAGE=true run-s build run_mocha coverage:report:text coverage:report:lcov",
         "run_mocha": "mocha 'lib/test/**/*.js' --timeout 100000 --bail --exit",
-        "compile:comment":
-            "Yarn workspaces do not link binaries correctly so we need to reference them directly https://github.com/yarnpkg/yarn/issues/3846",
-        "compile": "node ../sol-compiler/lib/src/cli.js",
-        "clean": "shx rm -rf lib ./contract_wrappers/generated",
-        "generate_contract_wrappers":
-            "node ../abi-gen/lib/index.js --abis  ${npm_package_config_abis} --template ../contract_templates/contract.handlebars --partials '../contract_templates/partials/**/*.handlebars' --output ./src/contract_wrappers/generated --backend ethers && prettier --write './src/contract_wrappers/generated/**.ts'",
+        "compile": "sol-compiler",
+        "clean": "shx rm -rf lib src/contract_wrappers/generated",
+        "generate_contract_wrappers": "abi-gen --abis  ${npm_package_config_abis} --template ../contract_templates/contract.handlebars --partials '../contract_templates/partials/**/*.handlebars' --output src/contract_wrappers/generated --backend ethers && prettier --write 'src/contract_wrappers/generated/**.ts'",
         "lint": "tslint --project .",
         "coverage:report:text": "istanbul report text",
         "coverage:report:html": "istanbul report html && open coverage/index.html",
@@ -42,6 +42,7 @@
     },
     "homepage": "https://github.com/0xProject/0x-monorepo/packages/contracts/README.md",
     "devDependencies": {
+        "@0xproject/abi-gen": "^0.2.13",
         "@0xproject/dev-utils": "^0.4.1",
         "@0xproject/tslint-config": "^0.4.17",
         "@types/lodash": "4.14.104",
diff --git a/packages/contracts/src/utils/chai_setup.ts b/packages/contracts/src/utils/chai_setup.ts
index 078edd309..1a8733093 100644
--- a/packages/contracts/src/utils/chai_setup.ts
+++ b/packages/contracts/src/utils/chai_setup.ts
@@ -4,7 +4,7 @@ import ChaiBigNumber = require('chai-bignumber');
 import * as dirtyChai from 'dirty-chai';
 
 export const chaiSetup = {
-    configure() {
+    configure(): void {
         chai.config.includeStack = true;
         chai.use(ChaiBigNumber());
         chai.use(dirtyChai);
diff --git a/packages/contracts/src/utils/crypto.ts b/packages/contracts/src/utils/crypto.ts
index 222cb7cca..80c5f30a5 100644
--- a/packages/contracts/src/utils/crypto.ts
+++ b/packages/contracts/src/utils/crypto.ts
@@ -18,7 +18,7 @@ export const crypto = {
     solSHA256(args: any[]): Buffer {
         return crypto._solHash(args, ABI.soliditySHA256);
     },
-    _solHash(args: any[], hashFunction: (types: string[], values: any[]) => Buffer) {
+    _solHash(args: any[], hashFunction: (types: string[], values: any[]) => Buffer): Buffer {
         const argTypes: string[] = [];
         _.each(args, (arg, i) => {
             const isNumber = _.isFinite(arg);
diff --git a/packages/contracts/src/utils/multi_sig_wrapper.ts b/packages/contracts/src/utils/multi_sig_wrapper.ts
index 84fed7944..41a1dd8d9 100644
--- a/packages/contracts/src/utils/multi_sig_wrapper.ts
+++ b/packages/contracts/src/utils/multi_sig_wrapper.ts
@@ -11,7 +11,7 @@ import { TransactionDataParams } from './types';
 
 export class MultiSigWrapper {
     private _multiSig: MultiSigWalletContract;
-    public static encodeFnArgs(name: string, abi: AbiDefinition[], args: any[]) {
+    public static encodeFnArgs(name: string, abi: AbiDefinition[], args: any[]): string {
         const abiEntity = _.find(abi, { name }) as MethodAbi;
         if (_.isUndefined(abiEntity)) {
             throw new Error(`Did not find abi entry for name: ${name}`);
@@ -33,7 +33,7 @@ export class MultiSigWrapper {
         from: string,
         dataParams: TransactionDataParams,
         value: BigNumber = new BigNumber(0),
-    ) {
+    ): Promise<string> {
         const { name, abi, args = [] } = dataParams;
         const encoded = MultiSigWrapper.encodeFnArgs(name, abi, args);
         return this._multiSig.submitTransaction.sendTransactionAsync(destination, value, encoded, {
diff --git a/packages/contracts/src/utils/token_registry_wrapper.ts b/packages/contracts/src/utils/token_registry_wrapper.ts
index 91bd5503d..86daeca62 100644
--- a/packages/contracts/src/utils/token_registry_wrapper.ts
+++ b/packages/contracts/src/utils/token_registry_wrapper.ts
@@ -9,7 +9,7 @@ export class TokenRegWrapper {
     constructor(tokenRegContract: TokenRegistryContract) {
         this._tokenReg = tokenRegContract;
     }
-    public async addTokenAsync(token: Token, from: string) {
+    public async addTokenAsync(token: Token, from: string): Promise<string> {
         const tx = this._tokenReg.addToken.sendTransactionAsync(
             token.address as string,
             token.name,
@@ -21,7 +21,7 @@ export class TokenRegWrapper {
         );
         return tx;
     }
-    public async getTokenMetaDataAsync(tokenAddress: string) {
+    public async getTokenMetaDataAsync(tokenAddress: string): Promise<Token> {
         const data = await this._tokenReg.getTokenMetaData.callAsync(tokenAddress);
         const token: Token = {
             address: data[0],
@@ -33,7 +33,7 @@ export class TokenRegWrapper {
         };
         return token;
     }
-    public async getTokenByNameAsync(tokenName: string) {
+    public async getTokenByNameAsync(tokenName: string): Promise<Token> {
         const data = await this._tokenReg.getTokenByName.callAsync(tokenName);
         const token: Token = {
             address: data[0],
@@ -45,7 +45,7 @@ export class TokenRegWrapper {
         };
         return token;
     }
-    public async getTokenBySymbolAsync(tokenSymbol: string) {
+    public async getTokenBySymbolAsync(tokenSymbol: string): Promise<Token> {
         const data = await this._tokenReg.getTokenBySymbol.callAsync(tokenSymbol);
         const token: Token = {
             address: data[0],