Weapon Maintenance Package: Weapon wear-and-tear and repair, additions and improvements.

Implements a system of weapon wear and tear for melee combat.
Weapons' rate of wear is dependent on their constituent material(s) and two new item flags.
Makes melee weapons' performance respect their current state of damage.
Most items can now be repaired and/or reinforced with the proper tools.
A new repair kit for some common non-sewing/non-soldering materials. Found near common tools.
Improves and expands firearms' wear and tear systems.
Firearms can be accurized with the proper tools and skill.
A small number of other fixes/optimizations.