represent bad states of signing key in ManageRepo view
Currently a repo is listed in a plain format when its working fine. If it is an unsigned repo, then it is marked with a red "Unsigned" subtitle. If you add a new repo with a URI that includes the fingerprint,
ManageRepo marks it as unsigned. It should show up like a regular repo, with no error subtitle.
Additionally, other signing key issues should be represented here via one of these subtitles. Like if there is a bad index signature, bad HTTPS cert, etc.