linqjs: Add definition files taken from the 3.0.3-Beta4 release

For a while now there's a *beta* version of linqjs (http://linqjs.codeplex.com/) that includes also d.ts files. The version is not backwards compatible. Because it's officially a "beta" I added it with the version number in place. 

I also added the linq.jquery.d.ts file which should work also for the older version.