Automatic Offline Testing timer (ticket #33)

I would like to introduce backward compatible option

-o on[,N]

where N specify the time in the form
<number>[<unit>]

Unit may be 's' for seconds or 'm' for minutes or 'h' for hours. Seconds assumed
when not present.

Missing N is assumed to be 4h to maintain backward compatibility.



git-svn-id: https://smartmontools.svn.sourceforge.net/svnroot/smartmontools/trunk@3018 4ea69e1a-61f1-4043-bf83-b5c94c648137