ServerChunkDataPacket is incorrectly encoding "Ground-Up Continuous" field

[ghost]

Currently it sets that field to true iff biomes are present. Instead it should be set to true if all 16 chunks are present and false if at least one of the chunks is null.

This was verified by connecting a vanilla mc client to a mcprotocollib server.

http://wiki.vg/Protocol#Chunk_Data

[ghost]

I think you need another check to ensure that biome data is present when all chunks are present to ensure that this is consistent.

My server was sending all chunks without biome data. MCProtocolLib did not throw any exceptions even though this broke it's assumptions. Because I wasn't sending the biome data this field was incorrectly set to false. The vanilla client would not accept the packets unless the field was set to true. Once I set that field to true the vanilla client did not require biome data to be present and loaded up the chunks without issue.