Random Event Overhaul

Alters the event controller based on http://baystation12.net/forums/viewtopic.php?f=5&t=10706.
Exception is that there is always some start time variance to prevent metagaming.

Mundane, moderate, and major events run on their own timers and start and run independantly of each other.
Multiple events of the same severity degree can run at the same time. However, currently only one instance of the same event can be active at a time.

code/controllers/master_controller.dm

@@ -360,6 +360,7 @@ datum/controller/game_controller/proc/process_pipenets()
 		Powernet.reset()
 
 datum/controller/game_controller/proc/process_nano()
+	last_thing_processed = /datum/nanoui
 	var/i = 1
 	while(i<=nanomanager.processing_uis.len)
 		var/datum/nanoui/ui = nanomanager.processing_uis[i]
@@ -371,15 +372,7 @@ datum/controller/game_controller/proc/process_nano()
 
 datum/controller/game_controller/proc/process_events()
 	last_thing_processed = /datum/event
-	var/i = 1
-	while(i<=events.len)
-		var/datum/event/Event = events[i]
-		if(Event)
-			Event.process()
-			i++
-			continue
-		events.Cut(i,i+1)
-	checkEvent()
+	event_manager.process()
 
 datum/controller/game_controller/proc/Recover()		//Mostly a placeholder for now.
 	var/msg = "## DEBUG: [time2text(world.timeofday)] MC restarted. Reports:\n"