Cleans up floors.dmi a bit and adds new turf decals.

_maps/map_files/debug/runtimestation.dmm

@@ -139,7 +139,7 @@
 /turf/open/floor/plating,
 /area/engine/gravity_generator)
 "av" = (
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/engine/gravity_generator)
 "aw" = (
 /turf/open/floor/plating,
@@ -344,13 +344,13 @@
 	req_access_txt = "11";
 	req_one_access_txt = "0"
 	},
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/engine/gravity_generator)
 "aY" = (
 /obj/machinery/light{
 	dir = 4
 	},
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/engine/gravity_generator)
 "aZ" = (
 /obj/structure/tank_dispenser{
@@ -621,23 +621,23 @@
 /area/hallway/primary/central)
 "bP" = (
 /obj/machinery/vending/cigarette,
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/hallway/primary/central)
 "bQ" = (
 /obj/machinery/vending/coffee,
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/hallway/primary/central)
 "bR" = (
 /obj/machinery/vending/cola,
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/hallway/primary/central)
 "bS" = (
 /obj/machinery/vending/snack,
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/hallway/primary/central)
 "bT" = (
 /obj/machinery/computer/arcade,
-/turf/open/floor/plasteel/black,
+/turf/open/floor/plasteel/dark,
 /area/hallway/primary/central)
 "bU" = (
 /obj/machinery/airalarm{
@@ -840,9 +840,10 @@
 /turf/open/floor/plasteel,
 /area/hallway/secondary/entry)
 "cy" = (
-/turf/open/floor/plasteel/loadingarea{
+/obj/effect/turf_decal/loading_area{
 	dir = 8
 	},
+/turf/open/floor/plasteel,
 /area/hallway/secondary/entry)
 "cz" = (
 /turf/open/floor/plating,