Refactors code to work with BYOND 500.

500 adds a "color" var to /atom, which conflicts with /obj/item/color, /obj/atmospherics/color and various simple_animals.
  /obj/item/color is now item_color
  /obj/atmospherics/color is now pipe_color
  simple_animals color is now body_color
Removes transformer.dm since it conflicted with transform() and was never used.

Signed-off-by: Mloc-Argent <colmohici@gmail.com>
Merge pull request #3700 from Mloc/byond500

Refactors code to work with BYOND 500.