Feature/logout button 43

[Toxsuh]

Issues

Closes #43

Description

• Adds logout functionality with logout button component, extended from button component
• clears user's authentication / session state without requiring page refresh
• Logged out users and admins can no longer access protected functionality
• User is directed to main homepage ONLY when current page is protected else user stays on page

Checklist

• Make sure you are requesting to pull a feature/fix branch (right side). Don't request the main branch!
• Make sure you are making a pull request against the main branch (left side). Also you should start your branch off main branch.
• I have added tests that prove my fix is effective or that my feature works.
• I have added the necessary documentation (if appropriate).

How To Review

View logoutbutton first!

Notes

Currently, we don't notify the user of system state changes when logging out. It's fine on protected pages because the user gets redirected, but maybe a pop-up notification when the user logs out on a non-protected page?