Add capability for Teachers and Admins to reset Student Passwords

[JAYKAY2291]

Summary

Admin and Teacher users should have the capability to reset passwords for student users

Things to Consider

As per #152, teacher users should be able to view students in their classes and so should only be able to reset passwords for students in their classes.

Criteria for Completion

• Admin users will be able to reset any student user password
• Teacher users will be able to reset the password of any student in one of their classes
• This feature should not be available to student users
• Add a test proving that it works