* fix failed tests on Windows #8737
* Use regexp literal instead of `RegExp` constructor so that we don't need to bother with escaping special character like `\` and `.`.
Note that by removing the path separator in regexp, I've relaxed the matching condition a little.Since there's little chance we have files like `XXXReact.d.ts`,it should not matter.
This reworks a few things in building and distributing React. The biggest change is using fbjs to share dependencies with other libraries. We're also using Gulp for some build steps.
