Add a reload button for the code timeline

[bnmnetp]

In support of the pair programming feature as well as the instructor code sharing feature it would be nice to avoid the step of reloading the page and simply reload the timeline.

I believe this would be relatively easy to do in activecode.js where we initialize the timeline.

[phattymcfee]

Could you expand on what/where the timeline is initialized in activecode.js?

[bnmnetp]

You are going to need to study the use and implementation of the addHistoryScrubber method. that is where we request the history and populate the data structures used by the slider.