[#31952] [#31952 ] Various language string updates for users

An updated PR for #1936, this is made against staging.

As for the en-GB.com_users.ini file, not sure what happened here, this whole PR was made in PhpStorm, go figure :)

This is for tracker: http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=31952&start=0