Only setup event handlers on the requests table once...

...instead of every creating/destroying handlers on every single button and row every refresh)

This shaves 300-500ms off of every requests table re-render (at least in my case when there are 100+ rows).

I only very lightly tested this (clicking on the viewJSON buttons), but I'm pretty sure this should be fine because all the handlers are doing `$(e.target).parents('tr')`.