set weechat notifications to expire

--- notify.py   2012-09-18 15:07:07.235164406 -0400
+++ notify-transient.py 2012-09-18 15:07:35.184505405 -0400
@@ -77,6 +77,7 @@
     wn = pynotify.Notification(chan, message, weechat.config_get_plugin('icon'))
     wn.set_urgency(urgencies[weechat.config_get_plugin('urgency')] or
             pynotify.URGENCY_NORMAL)
+    wn.set_hint('transient', True)
     wn.show()

 # vim: autoindent expandtab smarttab shiftwidth=4