Using /missing without any additional argument no longer gives a long java error in the console

Added:
/missing toggle - toggles the showing of the missing time in join messages.

When you hover over the time, you will now be able to see the exact date the player has left.

Fix: Player name no longer show as command arguments when they are not needed.

- /missing_list and /missing_remove are replaced by /missing list and /missing remove

- Added Tab Completion.

Added a command /missing_remove which allows operators to remove people from the missing list.

Fixed a typo.