Fix issues with air alarms:

+ Air alarms now support monitoring presets, including Vox and server presets.
 + Air alarms no longer refresh constantly when NOT on the main screen.
 + Reworked scrubber interface, added ability to scrub O2 (for Vox players)
 + Attempt at fixing firedoors.

code/ATMOSPHERICS/components/unary/vent_scrubber.dm

@@ -18,6 +18,7 @@
 	var/scrub_CO2 = 1
 	var/scrub_Toxins = 0
 	var/scrub_N2O = 0
+	var/scrub_O2 = 0
 
 	var/volume_rate = 120
 	var/panic = 0 //is this scrubber panicked?
@@ -70,8 +71,9 @@
 				"scrubbing" = scrubbing,
 				"panic" = panic,
 				"filter_co2" = scrub_CO2,
-				"filter_toxins" = scrub_Toxins,
+				"filter_tox" = scrub_Toxins,
 				"filter_n2o" = scrub_N2O,
+				"filter_o2" = scrub_O2,
 				"sigtype" = "status"
 			)
 			if(!initial_loc.air_scrub_names[id_tag])
@@ -121,6 +123,9 @@
 				if(scrub_CO2)
 					filtered_out.carbon_dioxide = removed.carbon_dioxide
 					removed.carbon_dioxide = 0
+				if(scrub_O2)
+					filtered_out.oxygen = removed.oxygen
+					removed.oxygen = 0
 
 				if(removed.trace_gases.len>0)
 					for(var/datum/gas/trace_gas in removed.trace_gases)
@@ -217,6 +222,11 @@
 		if(signal.data["toggle_n2o_scrub"])
 			scrub_N2O = !scrub_N2O
 
+		if(signal.data["o2_scrub"] != null)
+			scrub_O2 = text2num(signal.data["o2_scrub"])
+		if(signal.data["toggle_o2_scrub"])
+			scrub_O2 = !scrub_O2
+
 		if(signal.data["init"] != null)
 			name = signal.data["init"]
 			return