Switch tether shuttles over to self-initializing shuttle paradigm

* Deleted shuttle_controller_vr.dm as it is no longer needed.  Using standard shuttle_controller.dm again - It has no map-specific info!
* Converted the former contents of shuttle_controller_vr.dm into proper shuttle datums that self-initialize for each of our shuttles!
* Converted the tether_backup shuttle crashing mechanic to support self-initialization also.

code/modules/shuttles/crashes.dm

@@ -6,6 +6,12 @@
 	var/list/crash_areas = null
 	var/crash_message = "Oops. The shuttle blew up."	// Announcement made when shuttle crashes
 
+/datum/shuttle/New()
+	if(crash_areas)
+		for(var/i in 1 to crash_areas.len)
+			crash_areas[i] = locate(crash_areas[i])
+	..()
+
 // Return 0 to let the jump continue, 1 to abort the jump.
 // Default implementation checks if the shuttle should crash and if so crashes it.
 /datum/shuttle/proc/process_longjump(var/area/origin, var/area/intended_destination, var/direction)