[orca-list] default voice setting not available

[黄冠能 <hgneng 163 com>]

Hi all,

I am using Ubuntu 16.04-beta. Orca become unusable after I run `orca -s` and save without doing any changes. 
There are a lot error message related to key ‘default’ not exists in voices. This can be reproduced in a 
clean Ubuntu 16.04 Live CD.

If I hack the python file and add default value {} to voices[‘default’], the issue can be workaround. 
However, there are many places need to changed.

I am new to Orca. Where is Orca’s setting file stored? Is there any simple way to setup default voice 
attribute to fix this issue?

Thanks a lot in advanced.

A sample error message:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/orca/orca.py", line 462, in loadUserSettings
    settings.voices.get(settings.SYSTEM_VOICE))
  File "/usr/lib/python3/dist-packages/orca/speech.py", line 183, in speak
    _speak(content, acss, interrupt)
  File "/usr/lib/python3/dist-packages/orca/speech.py", line 164, in _speak
    _speechserver.speak(text, __resolveACSS(voice), interrupt)
  File "/usr/lib/python3/dist-packages/orca/speechdispatcherfactory.py", line 451, in speak
    self._speak(text, acss)
  File "/usr/lib/python3/dist-packages/orca/speechdispatcherfactory.py", line 328, in _speak
    self._apply_acss(acss)
  File "/usr/lib/python3/dist-packages/orca/speechdispatcherfactory.py", line 266, in _apply_acss
    and acss == settings.voices[settings.DEFAULT_VOICE]:
KeyError: ‘default'

Regards,

Cameron