Landmark Shuttles (#8512)

The lifeless live again. Or in this case, what never actually lived here.

Ports Baystation12/Baystation12#17460 probably for real this time. What this allows us to do is create shuttles on runtime and make shuttles easier by just making landmarks and a shuttle instead of areas and shuttles. Also allows runtime landmark creation via flares or whatever AND allows shuttles to use different landmarks at will.

I removed most of the overmap stuff, I think. It shouldn't be hard to slam it in whenever we need to.

Changes:

    "Shuttle code has been completely reworked."
    "Shuttles can now be modified to have more than one destination."
    "Shuttles now have a takeoff sound."
    "You can now throw mobs against walls to damage them. A lot."
    "You now need a neckgrab to throw mobs."
    "BEING UNBUCKLED DURING SHUTTLE LAUNCH IS DANGEROUS! Don't do it."
    "Adminghosts can now interact with all shuttles."

code/modules/mob/mob_movement.dm

@@ -164,7 +164,6 @@
 
 		src.move_speed = world.time - src.l_move_time
 		src.l_move_time = world.time
-		src.m_flag = 1
 		if ((A != src.loc && A && A.z == src.z))
 			src.last_move = get_dir(A, src.loc)