added alpha attribute to canvas graphics
Merge pull request #72 from CyberCRI/graphics-alpha

Added alpha attribute to canvas graphics
Log function is passed as arguemnt to runStep(). Fixes #53
Merge pull request #73 from CyberCRI/log-runstep

Log function is passed as argument to runStep(). Fixes #53
keyboard rotation working
Merge pull request #74 from CyberCRI/rotate-pieces

Keyboard rotation working
Merge branch 'master' into piece-positioning
player can move pieces or drag and drop them; fixed crash on light path computation