gmod_game: Fixed bad ammo drop trace that was breaking things..

Revision 793
Fixed bad ammo drop trace that was breaking things.
SWEP base now uses tracer name set in SWEP.Tracer, if any.
Changed Files:
[ul]
[li]trunk/gamemodes/terrortown/entities/weapons/weapon_tttbase/shared.lua[/li][li]trunk/gamemodes/terrortown/gamemode/weaponry.lua[/li][/ul]
Committed By Stefan van der Meer

-snip-