Add an option to Staff users to only allow access to students that have been assigned to them as their counselor

To adhere to FERPA restrictions, Staff with the Counselor role that are truly Counselors should only be able to view students that they have been assigned to. This should probably be an option though because some Staff users with a Counselor role may legitimately need to access all students or they may not want to define the Counselor for every student.