This license change is aimed at maximizing the reusability of this code
in other projects. VisualEditor is more than just an awesome editor for
MediaWiki, it's the new editor for the entire internet.
Added license and author files, plus mentions of the license to all
VisualEditor PHP, JavaScript and CSS files. Parser files have not been
modified but are effectively re-licensed since there's no overriding
license information. 3rd party libraries are not changed, but are all
already MIT licensed.
Change-Id: I895b256325db7c8689756edab34523de4418b0f2
