WIP collision debug
Don't clear if there's no pixels for current frame
Visual debugger. Switch on with F5, tick with spacebar.
Clear texture cache for debug surface printing.
Better way for disabling cache for video surfaces
Toggleable debugging layer
Har.c cleanups
Don't compiler har_debug if DEBUGMODE is not set
Merge pull request #251 from omf2097/adt-cd-debug

Debugging junk