* softwarecenter/backend/aptd.py: - do not crash if trans.error is None (LP: #761642) * softwarecenter/view/appdetailsview_gtk.py, softwarecenter/view/appdetailsview.py: - fix flickering during purchase install by more carefully checking if the app just became availalbe * utils/get_reviews_helper.py, utils/get_review_stats_helper.py: - fix crash when the server returns a API error (LP: #761452) - fix pyflakes warnins * softwarecenter/db/reviews.py: - ensure pkgname is a str (and not unicode), otherwise glib.spawn_async crashes (LP: #761357) * softwarecenter/backend/zeitgeist_simple.py: - do not crash if a zeitgeist has no subjects (LP: #761905)