Add Ability to Block People

It would be nice to add the ability to block people from seeing each other on Populi in the event there are two students that have issues with each other specifically but get along with other students.  In addition, to be able to divide classes into discussion groups and change those groups up for future modules/discussions would be nice as well.

Also, along those lines, it would be nice to extend the same to faculty/administrators as well - if there was an incident that needs to be handled but in the interim the faculty need to pause interactions but both still need to work, a way to pause interactions would be a nice addition.

Thank you.