Added maxSeconds prop, where timer starts or 'started'

[Zarux]

Added a prop to tell where the timer should start or where it "originally started".

<ReactCountdownClock seconds={30} maxSeconds={60} /> Will have the timer started halfways.

<ReactCountdownClock seconds={60} maxSeconds={30} /> Will not animate until 30 seconds left

Fiddle (converted to js): https://jsfiddle.net/6wgjyqyk/ Video example

I use the timer in a multiplayer game, and when a new client joins there is no way to display how much time has passed, only how much is left. This feature would help with that.