added platform monitoring content
added platform monitoring content

influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com,influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com,influxdb/docs.influxdata.com