Removing requirement to restart game after applying changes to mouse focus option

I have removed the requirement for the game to be restarted after applying changes to the 'lock mouse to window' option in the 'Input' tab of the settings menu. I had to add a bit of plumbing between IGraphicsDevice and SettingsLogic to achieve this.
Please cut down the whitespace as much as possible.
For single line comments we use `//` instead of `/* */`.