TNL-931: Eventing for Student Notes.

@mulby, @jmclaus  please review.
> don't we have to emit this with async == false?
> 
> I don't want to lose events because the browser drops the XHR when it redirects...

@mulby 
As you can see, we prevent default behaviour (line 48). Thus, when the user clicks on the link, we're sending a request and redirect the page manually (see redirectTo method) after getting back either successful or wrong response.
What do you think about adding some timeout on ajax response here?