Test setup helper added (#1482)

* signing prefix added

* Minor improvement

* Tests changed

* Successfully tested

* Minor improvements

* Minor improvements

* Revert "Dangling commas are now required. (#1359)"

This reverts commit a6889776f4.

* updates

* fixes #1404

* approve failing test

* suggested changes done

* ISafeERC20 removed

* conflict fixes

* fixes #1205

* minor change

* suggested changes

* reviewed changes

* final update

test/helpers/setup.js

@@ -0,0 +1,9 @@
+const chai = require('chai');
+
+const BigNumber = web3.BigNumber;
+const should = chai.use(require('chai-bignumber')(BigNumber)).should();
+
+module.exports = {
+  BigNumber,
+  should,
+};