This feature addressed two inventory issues:
1. Players carrying amount of weapons that shouldn't be allowed by the
weight limit.
2. Players carrying two variants of the same gun.
For example carrying both M32 and camo M32.
Single and dual version of the same weapon are also considered
the same gun, so you can't carry both MK23 and dual MK23 or
dual handcannons and golden handcannon.
This feature fixes several issues related to the selling price of both
single and dual pistols, all originating from the existence of dual weapons.
Most notable issue is the ability to "print" money by buying and
selling pistols in a certain way.
It fixes all of the issues by manually setting pistols'
'SellValue' variables to proper values.
