Refactor Roles

[ashayp22]

• HIApplicationStateController.isGuest is badly named since isGuest is set to true if the user is a guest AND a staff member. Change the name to something better, like isGuestOrStaff?
• Why are there so many Role structs? We should look into any Role or Attendee structs or variables that are badly named or are no longer being used.
• For the test account that we use, the API returns the Attendee, Staff, Applicant, and User role. Why is this happening? Was happening because the test account has both the Staff and User role. No other accounts should have this.