Change init template, notifies, and service definition to use an attribute for service name
Change all references to nagios-nrpe-server in the init to use the attribute

This fixes a long standing bug where NRPE couldn't be stopped on RHEL
systems because the killproc uses the nagios-nrpe-server name
Add new server_name attribute per install type and OS version

Only debian with packages is nagios-nrpe-server.  Source installs or
RHEL package installs are nrpe