A Time::Cloc> object is a twenty-four hour clock with nanosecond
precision (dependent on the base OS support, see Time::HiRes) 
and wrap-around.  It is a clock only; it has absolutely
no concept of dates.  Vagaries of date/time such as leap seconds
and daylight savings time are unsupported.

Time::Clock objects automatically stringify to a user-definable format.
