Added Biomes, flag --world-void, and some improvements

[STBrian]

I added another class for EmptyChunk that is a wrapper for anvil.EmptyChunk that handles biomes data in a chunk
The biomes data from BlockData is converted from PE biome column to the Java 1.16 biome section and is exported together when the chunk is saved

Another changes are:

• I changed the json module used to json5 to allow comments in blocks.json
• I renamed blocks.json to blocks.jsonc (to allow vscode auto-detect format)
• I added code to modify the level.dat, some things were deleted like gamerules, datapacks, player data.
• Other things like WorldGenSettings are deleted if the flag --world-void is not used. This is to allow the user decide whether if they want a void world or not (a world that generate new chunks)
• I also changed the assert assert len(data) == len(self.raw_decompressed) in classes.py to only show a warning cause some worlds fails that assert but still converts fine
• I changed a bit the conversion progress, now it will convert by regions and save it instead of convert all chunks and then saving regions; the reason is to reduce the memory usage (although it only reduces slightly)
• I fixed the block position printed for the unknown block message
• I fixed some blocks

[STBrian]

I forgot to say that I also fixed more blocks xd (oh wait, I could just edit the description)

[Anonymous941]

cc @Cracko298