[MIRROR] Clean snow, lavaland, and thunderdome (#1261)

* Clean snow, lavaland, and thunderdome

* Delete mining.dm.rej

code/game/area/areas/centcom.dm

@@ -37,6 +37,7 @@
 	dynamic_lighting = DYNAMIC_LIGHTING_FORCED
 	requires_power = 0
 	has_gravity = 1
+	flags = NONE
 
 /area/tdome/arena
 	name = "Thunderdome Arena"
@@ -75,6 +76,7 @@
 	requires_power = 0
 	has_gravity = 1
 	noteleport = 1
+	flags = NONE
 
 //Abductors
 /area/abductor_ship
@@ -83,6 +85,7 @@
 	requires_power = 0
 	noteleport = 1
 	has_gravity = 1
+	flags = NONE
 
 //Syndicates
 /area/syndicate_mothership
@@ -92,6 +95,7 @@
 	has_gravity = 1
 	noteleport = 1
 	blob_allowed = 0 //Not... entirely sure this will ever come up... but if the bus makes blobs AND ops, it shouldn't aim for the ops to win.
+	flags = NONE
 
 /area/syndicate_mothership/control
 	name = "Syndicate Control Room"

code/game/turfs/simulated/floor/plating/asteroid.dm

@@ -322,6 +322,7 @@
 	slowdown = 2
 	environment_type = "snow"
 	sand_type = /obj/item/stack/sheet/mineral/snow
+	flags = NONE
 
 /turf/open/floor/plating/asteroid/snow/airless
 	initial_gas_mix = "TEMP=2.7"