[Ohrrpgce] SVN: teeemcee/7985 Some backends.bas cleanup; add separate backends.bi.

[subversion at HamsterRepublic.com]

teeemcee
2016-05-01 03:47:47 -0700 (Sun, 01 May 2016)
162
Some backends.bas cleanup; add separate backends.bi.

Annotated all private functions in backends.bas with "private",
and moved some module-level code into a sub.
---
U   wip/allmodex.bas
U   wip/backends.bas
A   wip/backends.bi
U   wip/custom.bas
U   wip/game.bas
U   wip/gfx.bi
U   wip/gfx_alleg.bas
U   wip/music_allegro.bas