Bools and returns super-pr (#53221)

Replaces like 70-80% of 0 and such, as a side effect cleaned up a bunch of returns
Edit: Most left out ones are in mecha which should be done in mecha refactor already
Oh my look how clean it is

Co-authored-by: TiviPlus <TiviPlus>
Co-authored-by: Couls <coul422@gmail.com>

code/modules/awaymissions/mission_code/Academy.dm

@@ -62,9 +62,9 @@
 
 
 /obj/singularity/academy
-	dissipate = 0
-	move_self = 0
-	grav_pull = 1
+	dissipate = FALSE
+	move_self = FALSE
+	grav_pull = TRUE
 
 /obj/singularity/academy/admin_investigate_setup()
 	return

code/modules/awaymissions/mission_code/Cabin.dm

@@ -122,8 +122,8 @@
 
 /datum/map_generator_module/snow/checkPlaceAtom(turf/T)
 	if(istype(T, /turf/open/floor/plating/asteroid/snow))
-		return ..(T)
-	return 0
+		return ..()
+	return FALSE
 
 /datum/map_generator_module/bottomlayer/snow
 	spawnableTurfs = list(/turf/open/floor/plating/asteroid/snow/atmosphere = 100)

code/modules/awaymissions/mission_code/stationCollision.dm

@@ -43,8 +43,7 @@
 	name ="retro laser"
 	icon_state = "retro"
 	desc = "An older model of the basic lasergun, no longer used by Nanotrasen's security or military forces."
-//	projectile_type = "/obj/projectile/practice"
-	clumsy_check = 0 //No sense in having a harmless gun blow up in the clowns face
+	clumsy_check = FALSE //No sense in having a harmless gun blow up in the clowns face
 
 //Syndicate sub-machine guns.
 /obj/item/gun/ballistic/automatic/c20r/sc_c20r
@@ -68,7 +67,7 @@
 /obj/item/gun/energy/laser/practice/sc_laser
 	name = "Old laser"
 	desc = "A once potent weapon, years of dust have collected in the chamber and lens of this weapon, weakening the beam significantly."
-	clumsy_check = 0
+	clumsy_check = FALSE
 
 /*
  * Safe code hints