Restructured ViewModel

HELLo_World.View/App.xaml

HELLo_World.View/App.xaml.cs

...orld.ViewModel/EventArguments/ChangeViewModelEventArgs.cs

...o_World.ViewModel/EventArguments/StartNewGameEventArgs.cs

HELLo_World.ViewModel/HELLo_World.ViewModel.csproj

HELLo_World.ViewModel/ViewModels/GameViewModel.cs

HELLo_World.ViewModel/ViewModels/MainViewModel.cs

HELLo_World.ViewModel/ViewModels/NewGameViewModel.cs

HELLo_World.ViewModel/ViewModels/SettingsViewModel.cs

HELLo_World.ViewModel/ViewModels/TitleScreenViewModel.cs