itemtest_unusual alpha1

Added new commands:
— Inventory/Created cosmetics parameter
Examples:
- !add hat unusual 17 0 true (Applies sunbeams effect to first hat that on character in the list)
- !add hat unusual 38 1 (Applies cloudy moon effect to second created hat in the list)
- !add hat unusual 38 1 false (Same as previous example)
- !remove hat effect 0 true (Removes unusual effect from first character's cosmetic in the list)
- !get hat info true (Prints in the chat character inventory's cosmetics)

— !add hat offset <offset value> <hat slot> [inventory or created] (Applies vertical position offset for unusual effect)
Examples:
- !add hat offset 20 0 true (Applies unusual effect offset to character inventory's cosmetic for 20 units height)
- !add hat offset 0 0 (Moves effect to the original position for first created hat in the list)
- !add hat offset 0 0 false (Same as previous example)

- Fixed some bugs
Added new commands:
— !add weapon killstreak/ks (Applies killstreak on target's weapon)
— !add weapon sheen (Applies killstreak sheen on target's weapon)
— !add weapon kseffect/killstreakeffect (Applies killstreak effect on target's weapon)
— !remove weapon killstreak/ks (Removes killstreak from target's weapon)
— !remove weapon sheen (Removes killstreak sheen from target's weapon)
— !remove weapon kseffect/killstreakeffect (Removes killstreak effect from target's weapon)
— !streak (Sets streak count)
— !help ks (Prints help killstreak info)
— !team (Changes target's team)

- Fixed computer_wall02 model visual bug
- Added small skybox room