I've changed the logic so that AjaxHelpers keeps
track of which requests have not yet had mock
responses sent. This ensures that every response
is handled before moving on to the next one,
rather than always handling the last request.
My intention is that this won't allow bugs to creep
in where a request isn't fired and instead the test
responds to an old request. It also should ensure
that extra events aren't accidentally fired.

Authors:
  - Daniel Friedman
  - Ben McMorran
  - Peter Fogg

TNL-1892

TNL-2384

Refactored Studio's PagingView to use RequireJS Text and moved it
to common so that it can also be used by LMS.