When Resetting Countdown Timer, Update Timer on Same-Screen Displayed Elsewhere

[Dan-Peck]

With #1607 completed, an additional feature enhancement could be useful in some scenarios where the same Screen is concurrently displayed on other devices. When the reset button is clicked on one of them, for Plus and Pro customers, we can add code to allow and execute the same timer update on the other Screens.

[Dan-Peck]

Merged in @ ef8bdc9 and added to the queue for upcoming release to the live site.