Add Disk I/O Latency stats

[VirtualYG]

Would it be possible to add IOstat "await" counter to the Disk portion of glances? This would add latency stats on the fly on the console which is very helpful.

[nicolargo]

Most of the time, Glances uses the PsUtil lib to grab system stats. It is the case for the DiskIO plugin and the current PsUtil version (5.2) did not expose "await" stats: http://psutil.readthedocs.io/en/latest/#psutil.disk_io_counters

Another thing: if PsUtil proposes this stats in future version where to display the information ? Space is limited...