[Compatability] Distant Horrizons support

[AlienXtream]

What do you want to change or add in the mod? Write here Distant Horrizons has an API that may allow (or be requested to provide required changes to allow) the fading in/out of the fake chunks DH uses. additionally, along side dithered alpha and distance based falloff (see #62 ) would hopefully allow improved seemless transitioning from real chunks to DH chunks