result: improve test coverage, drop QATracker stuff, fix matches
    
    This is mainly test coverage improvement, but comes with a couple
    of code changes: we drop all the QATracker stuff as it never
    really went beyond being a proof of concept I used to troll Jono
    and it has no test coverage and I don't want to write it. We also
    fix the `ResultRow.matches()` method return value for the case
    where the other object isn't a ResultRow - `NotImplemented` was
    only correct back when this was `__eq__`, which it stopped being
    a long time ago.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>