Updated storage engine doc
Updated storage engine doc

influxdb/docs.influxdata.com,Tomcat-Engineering/docs.influxdata.com,Tomcat-Engineering/docs.influxdata.com,influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com,influxdata/docs.influxdata.com,influxdata/docs.influxdata.com,Tomcat-Engineering/docs.influxdata.com,influxdata/docs.influxdata.com,influxdb/docs.influxdata.com