GNOME PackageKit 3.8 RC Fixes Various Issues

GNOME PackageKit 3.8 RC is here to fix six bugs, which were found in previous Beta releases; as such, GTK deprecated functions are no longer used, the confirmation dialog is no longer displayed by default, horizontal scrollbars are no longer used, dialog alignment was repaired, the selection-changed is ignored after clearing, and the term software is used more consistently.