Added StreamSource and FileSource Dependency properties which can be set in XAML

Added StreamSource to MuPdfWrapper to support passing a Stream to the MuPdf

Removed need for ThirdParty lib MouseKeyboardActivityMonitor by using WPF  - Set background on panel to ensure mouse events are captured

Removed DispatcherTimer which waited an arbitrary 150ms with replace with Dispatcher.BeginInvoke using Bakcground priority
Added key file for Strong Naming Assembly
Removed referenece to System.Windows.Forms - no longer needed