Fix message pipes (and therefore Final Fantasy Tactics)

Updates tests.  Accept hrydgard/pspautotests#92 first.

Additionally:
 * Adjusts some logging, to make scheduling things more obvious in logs.
 * Makes invalid sema/etc. debug since it's finally been a while since one has been useful.

This fixes Final Fantasy Tactics dying after one of the first fights, and savegames not loading.  I suppose it could also help either Star Ocean, but doesn't seem to.  I don't know of many games which even use this feature, unfortunately.

All the message pipe tests pass.  They ended up kinda complicated, which is why I avoided them until now...

-[Unknown]