Feedback improvements

The game has been updated with a few quality of life improvements:

* Guidmode is a thing; Press and hold "TAB" to activate or deactivate guidemode. 

* It is more clear to first players that the 3 rooms initially are Tutorial Rooms

* The Pause Menu "Exit Function" now returns to startscreen, instead of exiting the game.

Thanks to all, for the valuable feedback and for playing :)