Implemented AssemblyName.ReferenceMatchesDefinition ()

I implemented this method by comparing the simple assembly names. This is the current behavior in MS.NET because of a bug in their implementation (see [Connect](https://connect.microsoft.com/VisualStudio/feedback/details/752902) bug report).

I added tests to verify the implementation and checked the results are the same on .NET 2.0 -> .NET 4.5.

Changes released under MIT/X11.