added React.JS

we aren’t using jsx (yet, anyway) bring it into a
module like anything else:

    define ['react'], (React) ->

There’s also a helper module to make building
your UI simpler at `compiled/withReactDOM`. It
safely moves everything from `React.DOM` to window
during a function call for convenience.

Change-Id: Ibf64f0b207411c31b92f30dddc6ce188d9462e11
Reviewed-on: https://gerrit.instructure.com/37376
Reviewed-by: Ryan Shaw <ryan@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: Ryan Florence <ryanf@instructure.com>
QA-Review: Ryan Florence <ryanf@instructure.com>