title: part of GtkLabel clickable
body: <p>How to do, that just a part of GtkLabel has a clicked event and calls a function.</p>
  
  <p>I make a twitter client, witch shows tweets and i would like to, when in the tweet is a # hashtag and I click it, the application shows a new window with search of this #hashtag. and I dont know how to do that just the #hashtag would invoke this event.</p>