Build application bundles in OSX

When doing install having built both renderer & engine, renderer will
be copied to correct location in bundle. May be a better to do this
with cmake. Still need to properly specify version info etc. of the
bundle. Possibly should include SDL2 in bundles, but don't really want
to have to have one copy for each engine.
tiny changes to fix xbox/gamecube changes
Port over Radix sorting for drawSurf from 2556d9d

Originally a port from iq3.
Fix some things broken in the Xbox removal commit that @xycaleth
pointed out. Should be the last of them.