[1.12.2] [Request] Add support for Overgrown Stone from Biomes O' Plenty

[Tank-Missile]

Currently, Overgrown Stone only uses the vanilla stone texture, which clashes with the added stones.

[kyeiti]

This should be added with other special block models (#6)

[jjc54]

An alternative to the overgrown stone issue that I thought of would be a truly "underground" mode for the modded stone types. This would ensure that any biomes like this would have stone on the surface as to not clash, but also that the modded stones are still accessible just by going underground.