Implements Stats

Stats is a client-side tool that helps support teams report what
kind questions they answer and their frequency.
Adds a stats monthly backup custom command.
Prevents a user from locking an issue indefinitely.

Previously, Stats gave users the right to lock issues indefinitely with
no expiration. This commit fixes that by settings a timer on each lock,
if the user takes more time than the one set in settings.CONFIG, his
page will refresh and unlock the issue for others to edit.