Update grunt-react to use react-tools v0.12.0
Because React's update from 0.11 to 0.12 contains breaking changes,
grunt-react should update its version accordingly.
Tests have been updated to reflect update React functionality:
- /** @jsx React.DOM **/ annotation no longer used
- js files will be transformed if valid React code is encountered
Merge pull request #40 from jackwanders/use-react-tools-0.12

Update grunt-react to use react-tools v0.12.0