Handle 404 errors from server
Handle 404 errors from server

Currently, any exception coming from the API Client is displayed
unfiltered. In some cases it is a good idea to handle them and
display them to the user in a more user-friendly way.

We are starting with 404 errors, which are usually caused by a URL
misconfiguration.

TG-1117 #close

Change-Id: I05f27e5b9b494a85d55660a4ae0bfc9256171402

javierpena/dlrnapi_client