* Update StandardToken.sol
* Slight improvement in gas efficiency
Users tend to attempt to over-spend more than they attempt to burn non-burnable tokens. If the contract checks for overspending before assuring tokens are not being burnt a slight amount of gas might be saved in the long term.
* Update to ganache-cli v6.1.0 and truffle v4.1.0
* Update to stable version of ganache-cli
* fix: update event emission warning
- Fix event emission warnings for solidity 4.21 after truffle has been
updated to use this version
* fix pr review comments
* update to truffle v4.1.5
* update package-lock
* add additional emit keywords
* update solidity-coverage to 0.4.15
* update to solium 1.1.6
* fix MerkleProof coverage analysis by testing through wrapper
* change version pragma to ^0.4.21
* fix solium linting errors