Tied with #47 whenever I get to it

With so many biomes being added in that as well as the current number of them, the current generation will no longer suffice. As it currently stands, biome generation works as such:

1. Pick a biome rarity
2. Pick a biome in that list of rarities
3. Zoom the biomes
4. Generate rivers

The flaw comes in with the second step, as more biomes in a list will mean less chance of that biome generating, especially with more rare biomes.

The proposal: change up how biome generation is done by giving the rare biomes a chance to generate. How this will be done is unknown, however it will mean that rare biomes will be patched "over" more common biomes. On top of this, some biomes are to be coupled with each other, so this is the proposed idea.

1. Generate a bunch of "common" biomes, then zoom 1 to 2 times, no more.
2. Randomly determine if "uncommon" biomes may generate, then zoom 2 times.
3. Generate "rare" biomes in "common" biome areas.
4. Generate "inner" biomes if the area has one. It must leave a border of the uncommon biome around. Zoom 2 to 3 times, no more.
5. Generate rivers.

This new layout will allow uncommon and rare biomes to have a chance to generate, as well as adding "inner" biomes to some biomes that may ask for it. As for the proposed "gold" biomes, this may still be in the air, but it may follow a similar process.