Copyable is now generic (as it probably was in the original COG)
convertNumber now requires type to derive from Number
tweak change to convertNumber signature
ConfigExpressionEvaluator is now a proper inner class
cosmetics
Tighten up a lot of the validator code in terms of types, type
parameters, generics, etc. This was stuff stripped by the compiler.
New features: <BiomeType name=""> for selecting biome dictionary
terms, <BiomeSet name="" inherits=""> for defining sets of biomes that
can be reused across distributions. Also, both <Biome> and <BiomeType>
now support climate restrictions, via 'minTemperature', 'maxTemperature',
'minRainfall' and 'maxRainfall' attributes.