improve efficiency
Merge branch 'master' of https://github.com/hcilab-um/STim

Conflicts:
	Src/STimWPF/App.xaml.cs
	Src/STimWPF/ContentWindow.xaml
	Src/STimWPF/ContentWindow.xaml.cs
	Src/STimWPF/Controls/ContentControl.xaml
	Src/STimWPF/Core.cs
	Src/STimWPF/Status/StatusController.cs