Convert from using Auth to Sentry, with a first pass at adding permissions to sidebar and key management
rename UserController to SessionController to make way for a UserController that manages users
add back UserController and corresponding views, this time to manage users
add note about having to run sentry migrations, also prevent a user from deleting himself
Fix a typo that causes non-superuser logins to not be able to view the List All Keys page
Move Sentry's migrations into the main folder, also update reminders to work with sentry (which also requires a migration)
Merge pull request #103 from omgninjaz/sentry

Sentry