Add DynmapForge support

[matthieuvdl]

I thought it was a good idea to create a mod version of ChunkyMap for dynmap forge, if it's not too complicated of course.
It would be really useful for a lot of people and server owners that are using sponge, mohist/magma server hybrids etc.

[leMaik]

Great idea! Mod blocks are not supported by Chunky but you could still render anything else.

[twixi]

Any ideas? me need too