url_image_preview.fix var name

url_image_preview/manifest.ini

 [info]
 name: Url image preview
 short_name: url_image_preview
-version: 0.3
+version: 0.4
 description: Url image preview in chatbox.
  Based on patch in ticket #5300:
  http://trac.gajim.org/attachment/ticket/5300.

url_image_preview/url_image_preview.py

@@ -84,7 +84,7 @@ class Base(object):
         mark = buffer_.create_mark(None, iter_, True)
         # start downloading image
         gajim.thread_interface(helpers.download_image, [
-            self.textview.account, {'src': url}], self._update_img, [mark])
+            self.textview.account, {'src': special_text}], self._update_img, [mark])
 
     def _update_img(self, (mem, alt), mark):
         if mem: