v5.2.1.03
 - Enhancement: Added the option for admin users to upload a csv file of names 
   and emails to whom invitations will be sent.  Thanks go to Phorum user 
   canadarules for suggesting this feature.
v5.2.1.02
 - Bugfix: Added missing end brackets to the settings.php file as reported and 
   patched by Phorum user KWood.
v5.2.1.01
 - Added invitation mode with 
    - the ability to enable moderators or users to send invitations 
    - the ability for moderator/user invitations to come from their personal email
    - the ability to allow visitors to request an invitation
    - the ability to set the number of days before an invitation expires
v5.2.1.00
 - Module started.
