Fix fuel doc version to 8.0
Fix fuel doc version to 8.0

Change-Id: I060eeeeeab0403e3806798491093498ad60cb9c5

stackforge/fuel-plugin-influxdb-grafana,stackforge/fuel-plugin-influxdb-grafana,stackforge/fuel-plugin-influxdb-grafana,stackforge/fuel-plugin-influxdb-grafana