Rewrite of check_ircd.pl (#1319)

I did a rewrite of the check_ircd.pl script to allow the script to 
* allow connections using SSL
* provide performance data

The options are downwards compatible and the script itself is used in our
infrastructure since more than a year now without any problems.

An example of a command definition:
```bash
define command {
    command_name check_ircd_ssl
    command_line $USER1$/check_ircd -H $HOSTADDRESS$ -w $ARG1$ -c $ARG2$ -s -p 6697
}
```

Please note that instead of the perl(Socket) module, the new script needs
perl(IO::Socket::INET6).

Left TODO: IPv6 support.
You can view, comment on, or merge this pull request online at:

  https://github.com/monitoring-plugins/monitoring-plugins/pull/1319

-- Commit Summary --

  * - rewrite of the plugin to support connections via SSL
  * enhance header section
  * - whitespace fix only
  * - prepare for release

-- File Changes --

    M plugins-scripts/check_ircd.pl (359)

-- Patch Links --

https://github.com/monitoring-plugins/monitoring-plugins/pull/1319.patch
https://github.com/monitoring-plugins/monitoring-plugins/pull/1319.diff

-- 
Reply to this email on GitHub:
https://github.com/monitoring-plugins/monitoring-plugins/pull/1319