Bugzilla plugin doesn't show error messages returned by the server

[emanchado]

When the Bugzilla server returns an error, did doesn't show anything, so the Bugzilla section disappears without any indication that there's anything wrong.

For example, making a mistake in the username will yield this result:

<Fault 504: 'The name [email protected] is not a valid username. Either you misspelled it, or the person has not registered for a Red Hat Bugzilla account.'>

Probably any non-success HTTP result should end up with did dying, or at least showing a prominent error message to the user.