Makes the .38 revolver smaller and less expensive. (#2947)

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## About The Pull Request

Not much more to say, makes the detective's revolver Small instead of
Normal so that it can fit in pockets and whatnot, and changes it's price
to 600 (as opposed to 1000 of before or the 750 of the flaming arrow)

## Why It's Good For The Game

The detective revolver as it currently stands is completely outclassed
by the Flaming Arrow and other pistols, this gives it a niche as a
backup weapon and or the cheapest handgun in the handgun easy to equip
to a large crew.
## Changelog

:cl:
balance: The detective's revolver is now priced at 600 credits instead
of 1000.
balance: The detective's revolver size is now Small.
/:cl:

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code/modules/cargo/packs/gun.dm

@@ -45,7 +45,7 @@
 /datum/supply_pack/gun/detrevolver
 	name = "Hunter's Pride Detective Revolver Crate"
 	desc = "Contains a concealable Solarian revolver, chambered in .38."
-	cost = 1000
+	cost = 600
 	contains = list(/obj/item/gun/ballistic/revolver/detective)
 
 /datum/supply_pack/gun/shadowrevolver

code/modules/projectiles/guns/ballistic/revolver.dm

@@ -472,6 +472,7 @@
 		"The Peacemaker" = "detective_peacemaker",
 		"Black Panther" = "detective_panther"
 		)
+	w_class = WEIGHT_CLASS_SMALL
 	manufacturer = MANUFACTURER_HUNTERSPRIDE
 
 	recoil = 0 //weaker than normal revolver, no recoil