feed-pqm should ask for my smtp password rather than making me write it in bazaar.conf

[Martin Packman]

If smtp_password is not set in bazaar.conf and you try to submit a branch, feed-pqm throws.

Traceback (most recent call last):
  File "feed-pqm", line 210, in ?
    sys.exit(main(sys.argv))
  File "feed-pqm", line 190, in main
    if send_mp(launchpad, mp, send_mail=not opts.nomail):
  File "feed-pqm", line 133, in send_mp
    SMTPConnection(config).send_email(message)
  File "C:\Python24\lib\site-packages\bzrlib\smtp_connection.py", line 165, in send_email
    self._connect()
  File "C:\Python24\lib\site-packages\bzrlib\smtp_connection.py", line 70, in _connect
    self._authenticate()
  File "C:\Python24\lib\site-packages\bzrlib\smtp_connection.py", line 117, in _authenticate
    self._smtp_password = auth.get_password(
  File "C:\Python24\lib\site-packages\bzrlib\config.py", line 1269, in get_password
    host=prompt_host, user=user)
  File "C:\Python24\lib\site-packages\bzrlib\ui\__init__.py", line 126, in get_password
    raise NotImplementedError(self.get_password)
NotImplementedError: <bound method SilentUIFactory.get_password of <bzrlib.ui.SilentUIFactory object at 0x01EDF5B0>>

If it prompted me for the password instead I wouldn't need it in plaintext on my drive.