In qtorrenthandle.cpp exception made caught by reference
In qbtsession.cpp exception made caught by reference
In rssdownloadrule.{cpp,h} 'RssDownloadRule::operator==' made const.
In smtp.cpp fix 'ct' reassign.
Force write settings to disk before exiting.
Fix notifications with xfce4-notifyd.
Merge pull request #1238 from botanegg/cppcheck

Corrections from running cppcheck.