some fix and new feature.

[Jiangshan00001]

the changelog:

1. add memory support for sapi.
   eg:

b = BytesIO()
engine.save_to_file('i am Hello World', b)
engine.runAndWait()

2. fix VoiceAge key error

3. fix for sapi save_to_file when it run on machine without outputsream device.

[nateshmbhat]

been away for quite some time now. can you please see if you can spend some time to resolve the merge conflicts ?

[willwade]

@nateshmbhat its not going to merge at all as its really referring to pyttsx4. But that aside I think voiceAge error and save_to_file when it run on machine without outputsream device is now fixed.

Im super intrigued about the memory support idea. Really @Jiangshan00001 was just wanting bytes back. I'll happily do a PR on this bit alone..

• Do we want it streaming or only on completion?
• Can you imagine a need for callbacks?

i.e. do we save_to_bytestream (like save to file) or do we save_to_bytestream and allow connect to work with this?