should give more useful feedback when user misspells librarything name

[eshellman]

When I erroneously enter AndromedaYelton rather than Andromeda_Yelton as my librarything username, the system acts as if it is obediently fetching my library and then nothing happens. (There is no user AndromedaYelton at librarything, so this should be failing somewhere. If it had failed with more useful feedback, I would not have spent days wondering why it wasn't loading my library. ;)