Dirt waters are more suitable for waterlilies
Add dedicated dunes biome in coniferous forest
Papyrus: use dirt base again
Force-place roots on mapgen tree schematics
Tune some humidity points to improve voronoi cells
Add random rotation to jungle trees
More complex distribution of dry grasses
Remove water below glacier rivers
Gravel as glacier seabed
Do not force-place acacia root
Tune acacia tree density
Match mgv5/v7 mushrooms to tree density
Spawn mgv6 mushrooms by trees
