Add a trusted organizations idea portal user type Merged

Today users with email addresses using the domains specified for internal portal users can self register for private idea portals. These domains can sometimes be used as a mix of the company domain, and customer domains so customers can self register to a private portal when SSO isn't used, and managing individual portal user lists isn't efficient.

With the introduction of private threaded portal comments, it would be useful to introduce a new type of portal user classification so internal users who truly are only "my company" domains can engage in those threaded comments.

Another option to specify other domains from trusted organizations that may also self register to the portal would be useful so private threaded comments are kept hidden from their view.