Admin: change titles in the user list

1.) Changed Pins column to be called Added. Added is the # of items added by the user. Change Repins to Added from.
2.) Removed Friends column, we will not have friends for launch. Just follows and followers.
3.) Added user's username, email in that table.
Table header row now is:  Name     Username     Email    Added    Added from   Followers   Follows     Date Created.