Updated the Documentation to use monitoring-plugins instead of nagios-plugins for debian/ubuntu based installations.
-----------------------|--------------------|---------------------------|----------------------------
RHEL/CentOS | nagios-plugins-all | [EPEL](https://fedoraproject.org/wiki/EPEL) | /usr/lib/nagios/plugins or /usr/lib64/nagios/plugins
SLES/OpenSUSE | monitoring-plugins | [server:monitoring](https://build.opensuse.org/project/repositories/server:monitoring) | /usr/lib/nagios/plugins
-Debian/Ubuntu | nagios-plugins | - | /usr/lib/nagios/plugins
+Debian/Ubuntu | monitoring-plugins | - | /usr/lib/nagios/plugins
FreeBSD | monitoring-plugins | - | /usr/local/libexec/nagios
OS X | nagios-plugins | [MacPorts](https://www.macports.org), [Homebrew](https://brew.sh) | /opt/local/libexec or /usr/local/sbin
Debian/Ubuntu:
- # apt-get install nagios-plugins
+ # apt-get install monitoring-plugins
RHEL/CentOS: