Add initial implementation of CollectionView and related types
Fix some access modifiers in of UIElement
Exclude some types from 4.0/4.5 profile
Types have been moved to System.Xaml.dll
Those types have been promoted to various dlls in mono.
Add missing public function
Fix 3.5 and 4.0 build profiles and add a gitignore
* uses dmcs * IUriContext resides in System.Xaml in .NET 4.0 and higher, hence adjust resp. Makefiles and conditionally build IUriContext.