* Do not create new NBT objects on Tile::getSpawnCompound()
* PocketMine's string formatting
* Remove more useless array indices and create lesser new NBT objects.
* Remove unused imports and type-hint Sign::setText() params
* Do not mess with Sign::setText() params due to #1204
* Fix formatting
* Make getSpawnCompound() final and add abstract addAdditionalSpawnData()
* Make the same changes for Bed tile
* Fix a missing "->" and remove some unneeded int casting.
- All entity and tile constructors now require a \pocketmine\level\Level instead of a \pocketmine\level\format\Chunk.
- Chunk->getProvider() and Chunk->setProvider() have been removed.
- Chunk::__construct() has had the $provider parameter removed.
- Chunk->unload() has had the unused $save parameter removed.
- ChunkEvents now take a Level parameter instead of going through the Chunk
API bump to 3.0.0-ALPHA4
