Adds the M579 Aerial-Defence System Carrier (AKA, the AA-APC, or LAV-AD of the future) #429

Icon difference rendering

Please file any issues here.

Icons with diff:

MODIFIED - icons/obj/vehicles/hardpoints/apc.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
quad_cannon (0)			Created
vls_launcher (0)			Created

MODIFIED - icons/turf/areas_interiors.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
apc_aa (0)			Created

MODIFIED - icons/obj/vehicles/hardpoints/tank.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
vls_launcher (0)			Created

MODIFIED - icons/obj/vehicles/interiors/apc.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
aa_back_2 (0)			Created
aa_back_1 (0)			Created
rear_wheel_R_aa (0)			Created
aa_back_3 (0)			Created

MODIFIED - icons/obj/items/weapons/guns/ammo_by_faction/uscm.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
quad_0 (0)			Created
quad_1 (0)			Created

MODIFIED - icons/obj/vehicles/interiors/general.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
viewport_terminal (0)			Created

MODIFIED - icons/obj/vehicles/movieapc.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
quadcannon_1 (0)			Created
vlslauncher_1 (0)			Created
vlslauncher_0 (0)			Created
quadcannon_0 (0)			Created