to activate the munin plugins
 - copy "osm_replication_lag" to "/usr/share/munin/plugins"
 - make "/usr/share/munin/plugins/osm_replication_lag" executable
 - symlink "/usr/share/munin/plugins/osm_replication_lag" to "/etc/munin/plugins"
 - copy "osm_replication.conf" to "/etc/munin/plugin-conf.d"
 - edit "/etc/munin/plugin-conf.d/osm_replication.conf" and set the workingDirectory
 - restart the munin-node
