Link a PlotLine to a Series
I cannot find a way to link a PlotLine (an average line, for example) to a specific series. I would like to be able to toggle the visibility of such a line with the visibility of a series. There's currently no way to do that easily, and I think that this would be a useful feature for a lot of scenarios.
You can link them together using event handlers like so: http://jsfiddle.net/yb18evpt/
Alternatively, we can use Annotations module, PoC: http://jsfiddle.net/BlackLabel/Luw0nhme/