quick_frontend, primitivus: fixes a couple of issues:

- chat: notification was raising an error when you just entered the room and self.nick is None
    - quick_widget: deleting a widget was modifying a dict while looping on it + unselect widget when it's being deleted

INSTALL

@@ -41,6 +41,7 @@ media_dir=~/sat/media/destination/path
 ### end sat.conf ###
 
 Of course, replace ~/sat/media/destination/path with the actual path you want to use.
+Check the wiki for more information about this configuration file: http://wiki.goffi.org/wiki/Configuration/en
 
 You should now be able to launch sat:
 	- to launch the backend, enter