Returns a new Timer with the same duration as this timer. Note that the cloned Timer will start now, and so will probably not expire at the same time as this Timer.

.clone( percentDone )

This is the same as the other clone method, except that the 'percentDone' parameter allows you to state how far along the Timer has expired. The value should be between 0.0, for no expiry, to 1.0, for it being completely expired.