ProtocolBlockTypePalette merged to BlockTypePalette

[madmaxoft]

The two objects were almost identical in functionality, so they were merged into a single one.

Fixes #4381.

[madmaxoft]

This is now ready for review.
The main points are:

• ProtocolBlockTypePalette functionality has been moved to BlockTypePalette and the ProtocolBlockTypePalette type removed completely
• BlockTypePalette can load the palette from strings / files, in three formats (described in the header):
  • blocks.json, as produced by vanilla server (so that new protocols' palettes can be added simply by users, rather than having to wait for us)
  • Regular TSV, a somewhat stripped version of the same data, produced by $/Tools/BlockTypePaletteGenerator; this file type is better suited for storage in the repository, rather than the raw blocks.json (550 KiB instead of 1.4 MiB; and avoiding possible copyright issues from Mojang)
  • Upgrade TSV, a special version of the regular TSV that uses BlockType + BlockMeta representation for the numeric IDs and is meant for upgrading pre-1.13 worlds (generated from Minutor data)

Note that the class is not yet used by the main codebase, so the only client code for it is the tests. THe first usage will come in a subsequent PR.

[NiLSPACE]

I didn't look at the huge files as I suspect they are generated. :)