Changes to layering of underfloor stuff:

- Disposal pipes are on layer 2.3
- Pipes and manifolds are on layer 2.4
- Cables are on layer 2.44
- Unary atmospherics stuff (vent pumps, scrubbers) are on layer 2.45
- Nav beacons, bluespace beacons and such things are on layer 2.5

It means that pipes appear below cables and 

git-svn-id: http://tgstation13.googlecode.com/svn/trunk@3097 316c924e-a436-60f5-8080-3fe189b3f50e

code/ATMOSPHERICS/components/unary/unary_base.dm

@@ -1,6 +1,7 @@
 /obj/machinery/atmospherics/unary
 	dir = SOUTH
 	initialize_directions = SOUTH
+	layer = 2.45
 
 	var/datum/gas_mixture/air_contents
 

code/ATMOSPHERICS/components/unary/vent_pump.dm

@@ -6,7 +6,6 @@
 	desc = "Has a valve and pump attached to it"
 
 	level = 1
-	layer = TURF_LAYER
 	var/area_uid
 	var/id_tag = null
 	power_channel = ENVIRON

code/ATMOSPHERICS/components/unary/vent_scrubber.dm

@@ -6,7 +6,6 @@
 	desc = "Has a valve and pump attached to it"
 
 	level = 1
-	layer = TURF_LAYER
 
 	var/id_tag = null
 	var/frequency = 1439

code/ATMOSPHERICS/pipes.dm

@@ -6,7 +6,7 @@ obj/machinery/atmospherics/pipe
 	var/volume = 0
 	var/force = 20
 
-	layer = 2.4 //under wires with their 2.5
+	layer = 2.4 //under wires with their 2.44
 
 	var/alert_pressure = 80*ONE_ATMOSPHERE
 		//minimum pressure before check_pressure(...) should be called
@@ -597,6 +597,7 @@ obj/machinery/atmospherics/pipe
 		var/obj/machinery/atmospherics/node3
 
 		level = 1
+		layer = 2.4 //under wires with their 2.44
 
 		New()
 			switch(dir)