repeat_mode not works on listen 0.6.1

[Mehdi Abaakouk]

when i activate repeat mode, close listen and restart it, listen does not start
the traceback:
{{{
  File "listen", line 200, in <module>
    ListenApp()
  File "listen", line 124, in __init__
    self.listen_instance = Listen()
  File "/usr/lib/listen/widget/listen.py", line 115, in __init__
    vbox.pack_start(self.get_main_menu(),False,False)
  File "/usr/lib/listen/widget/listen.py", line 468, in get_main_menu
    if config.getboolean("setting","repeat_mode"): b1.activate()
NameError: global name 'b1' is not defined
}}}

in the .config/listen/config if i changed "repeat_mode" true to "repeat_mode false"
listen start and works perfect

This ticket was migrated from the old trac: re #901
Originally reported by: ktalog