Made Firechat catapult-enabled

@drtriumph - Please review and merge. Here is a list of things I did:

* Updated `package.json` and `bower.json` to be consistent with our other open source repos.
* Changed all version numbers to `0.0.0` so Catapult can handle version bumps.
* Updated `.gitignore` to now include the `dist/` directory which brings it in line with our other repos.
* Minor updates to `README.md`.
* Added our MIT license.
* Renamed `firechat-default.*` to `firechat.*`.
* Added changelog.
* Updated a few things in the Grunt file.

I also updated Catapult so this should be ready to go. I will deploy v2.0.1 once this gets merged in and you are happy with it.

cc/ @vikrum - FYI