fix bugs in aisequence::execute
Merge remote-tracking branch 'upstream/master'
fix bug at http://bugs.openmw.org/issues/1155

Though it still can happen sometimes but not in such stupid manner.
fix bug http://bugs.openmw.org/issues/1335 (1304 as well)

though fish detects if actor is swimming, but in MW it attacks even if
the player is knee-deep in water
Merge remote-tracking branch 'mrcheko/master'
minor cleanup and silenced a warning
Merge remote-tracking branch 'scrawl/master'
Merge remote-tracking branch 'scrawl/master'
PcJoinFaction and friends: make sure the given faction exists
Implement modFactionReaction instruction (Closes #1347)