Merge pull request #9601 from Ghommie/Ghommie-cit265

Ports move force and move resist, movement/pushing/pulling tweaks & co.

code/game/machinery/doors/door.dm

@@ -5,6 +5,7 @@
 	icon_state = "door1"
 	opacity = 1
 	density = TRUE
+	move_resist = MOVE_FORCE_VERY_STRONG
 	layer = OPEN_DOOR_LAYER
 	power_channel = ENVIRON
 	max_integrity = 350

code/game/machinery/shieldgen.dm

@@ -4,6 +4,7 @@
 	icon = 'icons/effects/effects.dmi'
 	icon_state = "shield-old"
 	density = TRUE
+	move_resist = INFINITY
 	opacity = 0
 	anchored = TRUE
 	resistance_flags = LAVA_PROOF | FIRE_PROOF | UNACIDABLE | ACID_PROOF
@@ -93,6 +94,7 @@
 /obj/machinery/shieldgen/proc/shields_up()
 	active = TRUE
 	update_icon()
+	move_resist = INFINITY
 
 	for(var/turf/target_tile in range(shield_range, src))
 		if(isspaceturf(target_tile) && !(locate(/obj/structure/emergency_shield) in target_tile))
@@ -101,6 +103,7 @@
 
 /obj/machinery/shieldgen/proc/shields_down()
 	active = FALSE
+	move_resist = initial(move_resist)
 	update_icon()
 	QDEL_LIST(deployed_shields)