Fixed a bug in relative time displaying where the number of years were put in place of the number of days. Also now won't show seconds if there is at least one minute of time.
Also improved efficiency of getting relative time (and a lot of other things).
Now only records DisplayNames if they are different from a player's username.
Will produce a NullPointerException if a new player joins the game and their username is the same as their displayname.
Tab-completing for a sub command will always show "INVALID_SUB_COMMAND".
Commands show incorrectly in help pages.