two bugs with buying ammo

[marchewka]

The following happened twice (with same character too):
- i choose a slingshot type on shop's display
- choose to buy it
- select amount lower than the max
- i pay the correct amount
- in my inventory i do not get the shots i bought, instead the amount of another kind of shots i already have in my inventory gets increased by the number of shots bought.


Another one with shots:
- i bought 9 shots of annihilation
- in my inventory it ot split into 2 separate stacks, containing 8 and 1 of the same kind of shot