Energy weapons rework

[swwu]

Reworked visual effects etc on a bunch of energy weapons, see http://smf.cataclysmdda.com/index.php?topic=3061.0

The short version:

• added an ammo_effects field to weapons, which will be appended to the ammo's own effects field when the weapon is fired.
• added a NO_AMMO flag for weapons, which causes the weapon to not consume or require ammunition when fired.
• added USE_UPS_20 and USE_UPS_40 flags for weapons that drain 20/12 and 40/24 UPS energy per shot, respectively.
• UPS energy drain from weapons fire has been moved to the per-shot loop in game::fire so that burst-fired weapons with USE_UPS can drain the proper amount of energy.
• added a pierce field to weapons that is added to the ammo's pierce field when calculating armor reduction. It's optional in the JSON (defaults to 0 if not specified). Also added item::gun_pierce(bool), which is essentially identical to item::gun_damage(bool) except it returns the pierce value.
• added plasma and laser weapon vfx, which uses ammo_effects and custom fields.
• make_gun_sound_effect() now makes different sounds for different volumes of energy weapons fire.
• all fusion pack weapons now use UPS power, and only the fusion gun still uses fusion packs as ammunition.
• tweaks to numbers in JSON for balance purposes.

[KA101]

It'd be nice to have fusion packs be useful for something other than powering a fusion gun--fusion guns aren't that common. Perhaps a recipe to disassemble them to plutonium cells, if that's not already in?

[swwu]

Yeah, AFAIK fusion packs already disassemble back into plutonium cells since the fusion pack recipe is reversible.