Some fixes in the demo version

Hi folks,

I just uploaded a new zip for the demo version of Theralite. So what was fixed?

• The mouse pointer will be turned off when the game starts. It will switch back on if you move or click the mouse,
• The help screen and credit screen got the proper scrollbar,
• I fixed the 'e' key behavior when you swap the active weapon and pickaxe when there was no active weapon set,
• The generic yes/no dialog should now also work with mouse input,
• and I fixed the player rotation by mouse on windowed and full screen mode.

Have fun playing the demo and feel free to give some feedback!