[MAP] Refactors the code to work with BYOND 500.  Big commit.

Var changes:
* /obj/item/var/color is now item_color
* /obj/machinery/portable_atmospherics/canister/var/color is now canister_color
* /obj/machinery/atmospherics/var/color is now pipe_color
* /mob/living/simple_animal/mouse/var/color is now body_color
* /mob/living/simple_animal/chicken/var/color is now body_color

Proc changes:
* /obj/machinery/door/proc/animate() is now do_animate()
* /obj/machinery/transformer/proc/transform() is now do_transform()

Map changes are due to pipe instances being changed from color to pipe_color

Signed-off-by: Mloc-Argent <colmohici@gmail.com>