Functions to add random stat boosts from Candy Heart, Soul Locket, Void, etc.

[TaigaTreant]

There are a few items in the game that grant random stat boosts upon doing a set task (picking up red hearts with Candy Heart, picking up soul hearts with Soul Locket, using Void on a passive item, etc.). However, we do not have the functions in the API currently to easily replicate these effects (such as Candy Heart/Soul Locket on custom heart pickups). It would be helpful if these functions were exposed.