Quick improvements

I have applied some quick fix for some of the points that I gain from feedbacks and could be easily managed, like:

 - Crosshair for aiming instead of mouse (PC)
 - Player initial positin on Tutorial level to show how to move 
 - ASDW or Arrow Keys are usable optionally, settings are not needed (PC)
 - minor updates on Level2 

Actually I am working on the be able to jump through platforms and top level of buildings (jump through in upward direction, while downward stop&stay on top).