v0.16

Changes:

- add check_ntp_offset
- add check_mailq
- add check_connections
- improve check_process output
- add check_process cpu metrics
- improve check_service linux performance
- add reload support for systemd service
- add metrics to check_os_version
- add metrics to check_snclient_version
- use state from metric checks for final result
- check_service: adjust default warn/crit condition if service argument is used (#72)
- fix using arguments in aliased checks (#69)
- fix metrics order when using check_nsc_web
- fix wrong path in logrotation on linux
- fix check_drivesize using percent thresholds