Integrate Zabbix support from https://github.com/johncanlam/zagstamon.
Map Zabbix 'info' status to 'unknown' instead of 'warning'.
Zabbix backend: return an error cleanly in case the server is unreachable instead of raising an uncaught exception. Code borrowed from the Thruk backend.
Show last update in Connected and Refreshing statuses. FIXME: make it more generic.
Cosmetic.
Merge branch 'last_seen' of github.com:nono-gdv/Nagstamon into last_seen
Merge branch 'zagstamon' of github.com:nono-gdv/Nagstamon into zagstamon
Merge pull request #77 from nono-gdv/last_seen

Last seen
some GUI code cleaning
Merge pull request #74 from nono-gdv/zagstamon

Zagstamon
further monitor type for actions stuff
use correct version of keyring 3.7 without customization
cleanup keyring mess
cleanup keyring mess part II
unmodified keyring works in windows
stop repeated sound notification if not necessary anymore
let repeating sound stop if there is nothing more to notify
added monitor type option to action settings dialog
finished monitor type option to action settings dialog
added monitor_type detection to popup menu