Removes oxygen_agent_b and volatile_fuel gases

- oxygen_agent_b wasn't used at all, except for filters which, for some reason filtered it in addition to phoron
- volatile_fuel was only used in two chemistry reactions as reaction result, it was replaced with gaseous phoron.

code/ATMOSPHERICS/components/trinary_devices/filter.dm

@@ -40,7 +40,7 @@
 	..()
 	switch(filter_type)
 		if(0) //removing hydrocarbons
-			filtered_out = list("phoron", "oxygen_agent_b")
+			filtered_out = list("phoron")
 		if(1) //removing O2
 			filtered_out = list("oxygen")
 		if(2) //removing N2
@@ -95,10 +95,10 @@
 
 /obj/machinery/atmospherics/trinary/filter/process()
 	..()
-	
+
 	last_power_draw = 0
 	last_flow_rate = 0
-	
+
 	if((stat & (NOPOWER|BROKEN)) || !use_power)
 		return
 
@@ -206,7 +206,6 @@
 		switch(filter_type)
 			if(0) //removing hydrocarbons
 				filtered_out += "phoron"
-				filtered_out += "oxygen_agent_b"
 			if(1) //removing O2
 				filtered_out += "oxygen"
 			if(2) //removing N2

code/defines/gases.dm

@@ -21,11 +21,11 @@
 /decl/xgm_gas/phoron
 	id = "phoron"
 	name = "Phoron"
-	
+
 	//Note that this has a significant impact on TTV yield.
 	//Because it is so high, any leftover phoron soaks up a lot of heat and drops the yield pressure.
 	specific_heat = 200	// J/(mol*K)
-	
+
 	//Hypothetical group 14 (same as carbon), period 8 element.
 	//Using multiplicity rule, it's atomic number is 162
 	//and following a N/Z ratio of 1.5, the molar mass of a monatomic gas is:
@@ -35,14 +35,6 @@
 	overlay_limit = 0.7
 	flags = XGM_GAS_FUEL | XGM_GAS_CONTAMINANT
 
-/decl/xgm_gas/volatile_fuel
-	id = "volatile_fuel"
-	name = "Volatile Fuel"
-	specific_heat = 253	// J/(mol*K)	C8H18 gasoline. Isobaric, but good enough.
-	molar_mass = 0.114	// kg/mol. 		same.
-
-	flags = XGM_GAS_FUEL
-
 /decl/xgm_gas/sleeping_agent
 	id = "sleeping_agent"
 	name = "Sleeping Agent"
@@ -50,10 +42,4 @@
 	molar_mass = 0.044	// kg/mol. N2O
 
 	tile_overlay = "sleeping_agent"
-	overlay_limit = 1
-
-/decl/xgm_gas/oxygen_agent_b
-	id = "oxygen_agent_b"
-	name = "Oxygen Agent-B"	//what is this?
-	specific_heat = 300	// J/(mol*K)
-	molar_mass = 0.032	// kg/mol
+	overlay_limit = 1

code/game/machinery/alarm.dm

@@ -69,7 +69,7 @@
 	var/datum/radio_frequency/radio_connection
 
 	var/list/TLV = list()
-	var/list/trace_gas = list("sleeping_agent", "volatile_fuel") //list of other gases that this air alarm is able to detect
+	var/list/trace_gas = list("sleeping_agent") //list of other gases that this air alarm is able to detect
 
 	var/danger_level = 0
 	var/pressure_dangerlevel = 0

code/game/machinery/atmoalter/scrubber.dm

@@ -17,7 +17,7 @@
 	var/minrate = 0
 	var/maxrate = 10 * ONE_ATMOSPHERE
 
-	var/list/scrubbing_gas = list("phoron", "carbon_dioxide", "sleeping_agent", "oxygen_agent_b")
+	var/list/scrubbing_gas = list("phoron", "carbon_dioxide", "sleeping_agent")
 
 /obj/machinery/portable_atmospherics/powered/scrubber/New()
 	..()

code/modules/reagents/Chemistry-Reagents/Chemistry-Reagents-Toxins.dm

@@ -58,7 +58,7 @@
 /datum/reagent/toxin/phoron/touch_turf(var/turf/simulated/T)
 	if(!istype(T))
 		return
-	T.assume_gas("volatile_fuel", volume, T20C)
+	T.assume_gas("phoron", volume, T20C)
 	remove_self(volume)
 
 /datum/reagent/toxin/cyanide //Fast and Lethal

code/modules/reagents/Chemistry-Recipes.dm

@@ -667,7 +667,7 @@
 /datum/chemical_reaction/napalm/on_reaction(var/datum/reagents/holder, var/created_volume)
 	var/turf/location = get_turf(holder.my_atom.loc)
 	for(var/turf/simulated/floor/target_tile in range(0,location))
-		target_tile.assume_gas("volatile_fuel", created_volume, 400+T0C)
+		target_tile.assume_gas("phoron", created_volume, 400+T0C)
 		spawn (0) target_tile.hotspot_expose(700, 400)
 	holder.del_reagent("napalm")
 	return