Mapster32: prototypical checker for wall loops, enabled partially.
Inspired by
http://forums.duke4.net/topic/7506-tror-question/page__view__findpost__p__199151
the corruption checker now checks for certain conditions of the loops of each
sector. Recall that CW loops are outer and CCW loops are inner.
- If a sector has no or more than one outer loop, count that as corruption
(level 4 and 3, respectively).
- (Disabled) For sectors with exactly one outer loop, check that all inner
ones are inside it. This is currently not compiled due to an asymmetry of
loopinside() for degenerate cases, similar to pre-r3898 inside().