README.md in cloudstack-nagios-0.6.2 vs README.md in cloudstack-nagios-0.7.0

@@ -101,9 +101,10 @@
   
    * memory - measure memory usage in percents
    * cpu - measure cpu usage in percent
    * network - measure network usage
    * rootfs_rw - check if the root file system is writeable
+   * disk_usage - check the diks space usage of the root volume
 
 Example:
 
 ```bash
 $ cs-nagios check system_vm network --host 10.100.9.161