Cargo Wire, runtime and inflatable fixes (#1268)

Fixes the APC in the cargo warehouse being unpowered
Fixes two runtime errors i reported
Fixes inflatable doors being unresponsive due to a sleep. Seperating the opening code off into a spawned child process has made it much more responsive

code/modules/mob/mob.dm

@@ -660,9 +660,9 @@
 		src << "<span class='warning'>It won't budge!</span>"
 		return
 
-	var/mob/M = AM
+	var/mob/M = null
 	if(ismob(AM))
-
+		M = AM
 		if(!can_pull_mobs || !can_pull_size)
 			src << "<span class='warning'>It won't budge!</span>"
 			return

code/modules/mob/mob_grab.dm

@@ -181,6 +181,8 @@
 //Updating pixelshift, position and direction
 //Gets called on process, when the grab gets upgraded or the assailant moves
 /obj/item/weapon/grab/proc/adjust_position()
+	if (!affecting)
+		return
 	if(affecting.buckled)
 		animate(affecting, pixel_x = 0, pixel_y = 0, 4, 1, LINEAR_EASING)
 		return
@@ -265,7 +267,7 @@
 		hud.name = "kill"
 		affecting.Stun(10) //10 ticks of ensured grab
 	else if(state < GRAB_UPGRADING)
-		assailant.visible_message("<span class='danger'>[assailant] starts to tighten \his grip on [affecting]'s neck!</span>")
+		assailant.visible_message("<span class='danger'>[assailant] starts to tighten \his grip on [affecting]'s neck!</span>")
 		hud.icon_state = "kill1"
 
 		state = GRAB_KILL
@@ -277,7 +279,7 @@
 		affecting.setClickCooldown(10)
 		affecting.losebreath += 1
 		affecting.set_dir(WEST)
-	adjust_position()
+	adjust_position()
 
 //This is used to make sure the victim hasn't managed to yackety sax away before using the grab.
 /obj/item/weapon/grab/proc/confirm()