Function: timeclock-when-to-leave-string

Return a string representing the end of today's workday.
This string is relative to the value of `timeclock-workday'. If
SHOW-SECONDS is non-nil, the value printed/returned will include
seconds. If TODAY-ONLY is non-nil, the value returned will be
relative only to the time worked today, and not to past time.

(fn &optional SHOW-SECONDS TODAY-ONLY)