Merge pull request #639 from bergerkiller/master

Compatibility with the Spout chunk coord removal commit
Add and partially re-implement entity spawning items

This commit combines all known Vanilla items that can spawn entities
upon interaction under one single Class that deals with this. It
can be further extended with onSpawn or similar methods so item materials
can better specify the properties of the spawned Entity. For now, there
is only an onThrown for throwable items.

Signed-off-by: Irmo van den Berge <bergerkiller@gmail.com>
Replace old manual metadata system with new automated MetadataComponent

In addition, also added the metadata that was missing for some entities.
All metadata is now automatically updated by comparing live and synched values.
Some of the old entity protocols have been removed as they ended up empty.
Minecart/Boat has been further implemented to properly shake/take damage.

Signed-off-by: Irmo van den Berge <bergerkiller@gmail.com>