Change NPCs to have their attack delay set in DB

This gives us a much more straight forward way of setting mob
attack delay with respect to live.

The attack_delay column is in 10ths of seconds, just like weapons are
The attack_speed is left for references for now.

zone/npc.cpp

@@ -248,6 +248,7 @@ NPC::NPC(const NPCType* d, Spawn2* in_respawn, float x, float y, float z, float
 	delaytimer = false;
 	combat_event = false;
 	attack_speed = d->attack_speed;
+	attack_delay = d->attack_delay;
 	slow_mitigation = d->slow_mitigation;
 
 	EntityList::RemoveNumbers(name);