Bunch of polishes, aswell as fixing up the grenade a bit and restoring the throw force multiplier

Various tiny, insignificant detail improvements!
-Improved the bullet models for the Pistol, SMG and especially the 357 revolver, which now has an entirely new speedloader that much more resembles the original one seen in Half Life 2
-Finally fixed the 357 revolver's ironsights to actually make them not useless. Now they're aligned properly and you can aim for headshots again.

-Finally added a functional trigger to the shotgun
-Improved some handposes for the pistol and changed the trigger finger on appropriate weapons to take on a "safe" handpose when idle (basically good trigger discipline, particularly for RP purposes)

-Grenade added back!
-Tweaked AR2 recoil
-Tweaked pistol damage (less overpowered, hopefully)