FPArms: many changes involving moving stuff into the first person arms VMDL for easier sharing & genericization (see commit comment) • removed hold_* bones • added weapon_root, weapon_root_children, weapon_IK_hand_*, and hand_*_to_weapon_ikrule, following the same hierarchy as existing weapons (weapon_root is a separate root bone) • weapon_root_children is a new bone between weapon_root and the children ("trigger", "magazine", etc. and the IK bones); this is so that weightlists can be moved into the arms VMDL instead of having to be explicitly defined in each weapon. Only part-specific weightlists (e.g. "mode_selector" for the MP5 knob) need to exist as part of weapon VMDLs now. • transferred common weightlists involving weapon_root • debug gizmo meshes (reminder: they're in a bodygroup) now show the weapon IK targets & the weapon_root bone • added "shared" animationlist prefab which holds generic template anims that weapons can reuse; the goal is to make these as independent from each other as possible (no interlocking references), more to come soon