Merge pull request #111 from clintbellanger/master

merge from master
npc requires_status and requires_not
update comments
Use a list of states for the requires[_not]_status in NPC

This is consistent with the quest events, which can have a list of
states as well. Maybe we should think about having that code only once
in a generic fashion.
Merge pull request #118 from stefanbeller/proposal772

NPC requires_status consistent to quest requires_status
Merge pull request #772 from RyanDansie/npc_requires_not

NPC requires_status and requires_not