Libbet and the Magic Floor v0.02

Highlights include a demo, more obvious indication of the exit, and sound effects. Size is 8848 bytes.

• Combine identical strips, saving a few bytes
• Fix head bob when rolling left
• Draw track and score updates using Popslide, a VRAM transfer buffer
• Draw exit arrows at top left and right of 8-cell-tall floors
• Fade from white at 90% and 100% completion
• Fade to white on exit
• Tutorial demo (press Select)
• Separate Libbet's elbows in push-off cel
• Sound effects
• Animate falling in a hole and being ejected