True Backpack (+ Quiver & Helipack)

Logic changes

• Now you should use the secondary button to put backpack's on ground;
• Crouch + Secondary Action: Transfers all items from the backpack to the chest.
• Crouch + Primary Action: Transfers all items from the chest to the backpack.
• Crouch + Use Action: Transfers all items from the backpack of the same type who has on chest to it.

Minor bug fixes:

• Backpacks no longer need to be equipped before being placed on the ground.
• Updated some cosmetic logic and removed deprecated usage.
• When a backpack is equipped, the quiver is now attached to the pelvis instead of the chest.
• Backpack no longer disapear when interact with a chest with it on hand;