Wrote test methods and validated ring buffer operation. RingArray can
now be used. Need to now do testing within the game.
So far (although much more testing will be needed) bonzo appears to be
respawning properly when dying across screens.

Still need to test the final case: bonzo crossing more than 5 screens
and having no choice but to respawn in bad place.
Updated debug world with fall content, as well as really, really long
fall. Ring buffer works as expected: after so much level history, it
stops remembering it and falls back to just respawning him and hoping
for best.