I should be able to open/close all Categories in the Documentation by Category page

Summary: Request from Eric -- he'd like a way to open all of the categories up, so he can use the browser's find-in-page.

Not at all clear how to implement this. My best guess, offhand, is that we could assign a class to all of the category _QLLinks, and add a mechanism for -- what? Activate all Gadgets with this class? Specifically toggle _QL controls open/closed? Need more use cases and more design.

Also, this is potentially problematic from a traffic POV, leading to a lot of simultaneous requests being sent to the server. Do we need to throttle those, or should it be okay?