Add better workaround for aura lag.

"Aura lag" (more properly "event lag") is what happens when you cast a
spell and there is some delay before the spell's effects are applied by
the game server and recognized by the client.

Deal with aura lag by persisting auras in the simulator that are applied
by a spell by at least the aura lag time, even if the spell has finished
casting and hit its target already.

git-svn-id: svn+ssh://svn.curseforge.net/wow/ovale/mainline/trunk@1413 d5049fe3-3747-40f7-a4b5-f36d6801af5f