prints a message in console when mouse button down or released
can click on a piece, which is then selected or prepared for drag and drop
Merge pull request #74 from CyberCRI/rotate-pieces

Keyboard rotation working
preparation for piece positioning
Merge branch 'master' into piece-positioning
player can move pieces or drag and drop them; fixed crash on light path computation
made right part of the board visible; put rotation amount into constants
put playable board dimensions in service
user-friendly names for margins
piece box on the right of the board (not interactive); drag and drop fix; style fixes
scaled pieces in box
fixed cloning error
refactoring origin
added boxed pieces (basics); made the code more defensive; small fixes
Merge branch 'master' into piece-positioning
removed offsets from services
Merge branch 'piece-positioning' of https://github.com/CyberCRI/gamEvolve into piece-positioning
Merge pull request #80 from CyberCRI/piece-positioning

Piece positioning
corrected bad reflection calculation
merged with master