[backends] zypp: Detect RPM database corruption for initializeTarget
Merge pull request #21 from thp/detect-corrupted-rpmdb

[backends] zypp: Detect RPM database corruption for initializeTarget
[packaging] Remove more obsolete Qt stuff from the .spec file
[refresh] Don't resolve URL in zypp_is_changeable_media

This avoids a network roundtrip and fixes a crash related to an uncaught
zypp::PluginScriptException (the alternative would be to handle the
PluginScriptException in zypp_is_changeable_media(), but as CD/DVDs
are not our top priority for distributing nemo, just handle it quickly.