rosie: handle QueryErrors and invalid prefix values

This adds handling to rosie go and rosie lookup for query errors as follows:

In case of an invalid prefix:
 * rosie go will now produce a dialog for invalid prefixes and not launch rather than just crashing out
 * rosie lookup will now produce a more helpful error message and exit rather than churning out traceback

QueryErrors and local suite statuses:
 * rosie go will now display a dialog and display empty results for the case of a QueryError raised by a get local suites query rather than crashing out.
 * rosie ls should produce a more helpful error message and exit rather than printing out traceback.