Update System.Windows.Interactivity.dll
Introducing NumericUpDown
Added Style
Format  Style xaml
Added NumericUpDown to Controls.xaml
Added to .project file of .NET4 and .NET45
Added example to MainWindow
Format Code
Fixed an issue with .NET45 project (accidently referenced the .NET40 project
IncrementValue and DecrementValue events had wrong RoutedEvent
Install Microsoft.Bcl.Async into the Demo so we can get rid of ContinueWith
Fix whitespace
Due to a limitation with Windows' windowing system, we can not change AllowsTransparency after a window has loaded. Fixes #853
Fix the .NET45 build of the demo
Write an explanation how we have async/await support on .NET 4.0
Merge pull request #854 from MahApps/bcl-async

Install Microsoft.Bcl.Async into the Demo so we can get rid of ContinueWith
Initial implementation of modal flyouts.
Respect the current theme for the overlay color.
Added modal Flyout support to CleanWindowStyle.
Add the latest features to the changelog