Add opened chests to openedChests.

Prevents chests from reproducing more and more items.
add initial world delete code
successfully deletes world folders
reset player statistics on start
Merge branch 'game-end'
Merge branch 'fixChests'
Fix player freeze glitchiness.

Only cancel move events if they are translations along the x or z axes.
Ignore any vertical movement (in case the players are spawned in the
air) or any rotational movement.
Teleport player back to previous location.

Player position used to be changed, causing the player to jump back and
forth between his real position and his new position. This should fix
that.
Merge remote-tracking branch 'eric/freezeFix'