Modified system menu show behavior

The system menu usually opens when the right mouse button is released (except for the window icon). In this package the menu is shown when the right mouse button is pressed.
corrected stretching of icons, fixes #1031
Update MetroAnimatedSingleRowTabControl.xaml

removing this margin, you can use TabStripMargin when the tabstripplacement is diferent of TOP!
Update MetroAnimatedTabControl.xaml

fix for metroanimatedtabcontrol
Update MetroTabControl.xaml

fix for the metrotabcontrol
Fixed an issue related to ToUpperConverter in the CleanWindow style. Added a glow to the CleanWindowDemo.
Fixes #1044
The GlowWindow was trying to update when it's host window's parent was trying to close the host window.
Fixes #954
Added support for ToggleButtons in WindowCommands and also modified WindowCommands code for supporting all ButtonBase controls.
Fixes #812
ProgressRing: In reality, people should just set IsActive to false if they are going to hide the control..... seriously.
MetroProgressBar: Stops trying to animate while the control is "invisible".
Converted spinkit-xaml to WPF + integration with MAM.

Missed reference to ProgressRing.xaml style file for .NET45.

Moved styles to Themes.