This fixes up a few regressions that occurred when we updated to jQuery

3.x:

$.fn.live(event) no longer exists, in favor of

$(document).on(event, selector).
Some reordering of event handlers made it so that the initial load of

  the news feed was finishing before masonry had been set up. I've added a

  guard to avoid calling reload unless we've done initial set up

  already.
The "events" form of $.load no longer exists. I've changed a use of

  it to just use the document ready event.

Loaded the admin site and played around with the dashboard without

seeing any errors pop up in the browser console.