Merge branch 'development' into fix/underscorePrivate

* development: (29 commits)
  Move call to error reporter to end of handler so that even if reporting the error takes a while, it doesn't block the UI
  Update outdated WETH ranges
  Fix conditional
  Fix top-padding
  Publish
  Update CHANGELOGs
  Add slashes to base URLs
  Fix linter issue
  Fix WETH symbol
  Update snapshot and artifacts
  Replace our EtherTokens with WETH9 from maker
  Fix test description
  Fix a typo
  Add err==null assertions
  Add WETH9 tests
  Use the new snapshot including WETH9 and it's artifacts
  Add WETH9 and mirations
  Fix WETH events watching
  Fix a typo
  Init the _etherTokenContractsByAddress
  ...

packages/0x.js/test/utils/token_utils.ts

@@ -17,6 +17,13 @@ export class TokenUtils {
         }
         return zrxToken;
     }
+    public getWethTokenOrThrow(): Token {
+        const wethToken = _.find(this.tokens, {symbol: WETH_TOKEN_SYMBOL});
+        if (_.isUndefined(wethToken)) {
+            throw new Error(InternalZeroExError.WethNotInTokenRegistry);
+        }
+        return wethToken;
+    }
     public getDummyTokens(): Token[] {
         const dummyTokens = _.filter(this._tokens, token => {
             return !_.includes([PROTOCOL_TOKEN_SYMBOL, WETH_TOKEN_SYMBOL], token.symbol);