Something wrong with the binding

In 5.4.0 version the test passed
Merge pull request #556 from maratoss/patch-1

Something wrong with the binding
Fix finding DependencyProperties declared in base classes

Conflicts:
	ReactiveUI.Platforms/Xaml/WpfDependencyObjectObservableForProperty.cs
Fix this for WinRT too, in a more nightmarish way

Conflicts:
	ReactiveUI.Platforms/Xaml/DependencyObjectObservableForProperty.cs
Backport to RxUI5
Bump MonoMac Rx version to current version
Version bump to 5.5.1
Adds NotifyPropertyChanged wrapper.
Update IReactiveNotifyPropertyChanged with the new interfaces.
Update IReactiveObject with the new interfaces.
Update Android classes.
Update Cocoa interfaces.
Update IReactiveNotifyCollectionItemChanged.
Fix style.
Update IROObservableForProperty to translate to ObservedChange.
ReactiveList also understands the new stuff.
Even ReactiveObject uses the new interfaces.
What is this stuff even doing here.
Fix invalid cast.
Merge branch 'binding-fixes' into indexer-bindings