Add package mvvmlight
Move ViewModel of Main to mvvm-light
Delete unused file
Move RelayCommand to MvvmLight
Remove NotifyPropertyChanged
Remove unused methods
Remove BooleanToInvisibilityConverter
Fix HighlightDarkColor
Use Set method from MvvmLight
Rename method
Remove redundant variable
Remove default constructor on MainViewModel, setup SimpleIoC
Merge pull request #131 from dirkrombauts/master

Migrate to MvvmLight