Gun_Melee rule: add non-stock weapons

Projectile: increase throwing accuracy
ExplosionBState: throwing Exp. for grenade hits
ProjectileFlyBState: proper quantity & Exp. for shotguns
TileEngine: conform Exp. for shotguns & grenade explosions
	prevent multi-Exp for expl; give Exp for any pellet hit.
	validateThrow(), normalize arc @ 0.78 period.
remove debug