Fixed not working packet decompression
Fixed not working packet decompression

A compressed packed contains always the uncompressed size, but in the code this size was threatened as the compressed data size. This created a failure, when the client compressed a packet.
See: http://wiki.vg/Protocol#With_compression
Fixes #2841
Fixes #2467

marvinkopf/cuberite,marvinkopf/cuberite,birkett/cuberite,marvinkopf/cuberite,QUSpilPrgm/cuberite,Fighter19/cuberite,Fighter19/cuberite,Altenius/cuberite,nounoursheureux/MCServer,QUSpilPrgm/cuberite,birkett/MCServer,marvinkopf/cuberite,Fighter19/cuberite,Frownigami1/cuberite,kevinr/cuberite,Fighter19/cuberite,Schwertspize/cuberite,kevinr/cuberite,mc-server/MCServer,birkett/MCServer,QUSpilPrgm/cuberite,birkett/MCServer,johnsoch/cuberite,tonibm19/cuberite,nounoursheureux/MCServer,johnsoch/cuberite,HelenaKitty/EbooMC,Frownigami1/cuberite,QUSpilPrgm/cuberite,Schwertspize/cuberite,nounoursheureux/MCServer,marvinkopf/cuberite,mc-server/MCServer,birkett/cuberite,nounoursheureux/MCServer,mc-server/MCServer,tonibm19/cuberite,Altenius/cuberite,birkett/MCServer,kevinr/cuberite,kevinr/cuberite,mc-server/MCServer,Haxi52/cuberite,birkett/cuberite,mc-server/MCServer,Fighter19/cuberite,QUSpilPrgm/cuberite,HelenaKitty/EbooMC,Schwertspize/cuberite,mc-server/MCServer,Haxi52/cuberite,birkett/MCServer,birkett/cuberite,tonibm19/cuberite,Frownigami1/cuberite,birkett/cuberite,HelenaKitty/EbooMC,johnsoch/cuberite,nounoursheureux/MCServer,Altenius/cuberite,tonibm19/cuberite,marvinkopf/cuberite,Frownigami1/cuberite,Haxi52/cuberite,tonibm19/cuberite,HelenaKitty/EbooMC,nounoursheureux/MCServer,HelenaKitty/EbooMC,Frownigami1/cuberite,Schwertspize/cuberite,tonibm19/cuberite,Schwertspize/cuberite,Altenius/cuberite,johnsoch/cuberite,Haxi52/cuberite,kevinr/cuberite,Haxi52/cuberite,johnsoch/cuberite,Altenius/cuberite,birkett/MCServer,Haxi52/cuberite,birkett/cuberite,kevinr/cuberite,QUSpilPrgm/cuberite,Fighter19/cuberite