Implemented checkbox widget draw function
Start decompiling gfx_fill_rect

Section starting 0x00678C83 complete and works, but needs better comments/names
Some tidying up. Scrollbars don't work
Formatting
Cross-hatching branch
Bug fix - memset doesn't increase pointer
Bug fix: cross-hatch loop was wrong

Also rename and tidy up a bunch of variables
Add author
Merge branch 'ZedThree-gfx_fill_rect' into gfx_unstable