Playerconnection opgeruimd
Wat functies opgedeeld om het netter te maken.
Only 1 powerup available on the player screen

If a new one is sent to the player while a powerup is still visible, it
will not create the new one.
Updated powerupController documentation
Updated ballController documentation
Updated player connection and player game documentation
Updated highscore documentation
Mainscreenconnection flink korter gemaakt. :D
Dit zijn alle nieuwe files
Merge branch 'ClientCleanUp' of https://github.com/olafmaas/contextprojectgroep6 into ClientCleanUp
Conflicts resolved