Clean up protocol

[thisryan]

The protocol uses different paradigms for different commands, this could be cleanup up although it is not striclty necessary:

• editEntity and editBossBar edit all the variables which are set
• setPlayerStat has to specifically receive a stat to be set

Additionaly it would be nice to cleanup the order of the arguments. The most important example is that on some commands playerIndex is first and on other not.