Error handling

[Samasaur1]

We essentially need to find (almost) every time that there's an unwrap() call in our code, and actually handle errors. If the server panics handling any request, the lock on the repositories is "poisoned" and so no other API calls will work. If we handle the errors, however, we can return an error code and release the lock, so that future API calls can still work without restarting the server