:bug: fix #11
Revert ":bug: fix #11"

This reverts commit ee6cc4ce43623cce7e896b23bd1acd470201f9c0.
:bug: fix #11

Fix this rather by remove the var definition since the functions are hoisted anyways.
Merge pull request #12 from despairblue/patch-1

Fix `contract.impl.js` when running under ES6.