Adds 1.14 (477) protocol support, based on:
https://wiki.vg/index.php?title=Pre-release_protocol&oldid=14723
* New packets: SetDifficulty, LockDifficulty, UpdateJigsawBlock, UpdateViewPosition, UpdateViewDistance
* New metadata: Optional VarInt (17) and Pose (18)
* Add new join game variant with view distance, without difficulty
* Add new server difficulty variant, with locked boolean
* Implement recipe parsing changes, add stonecutting recipe type