Implement emacspeak protocol for speech servers.

[derekriemer]

Emacspeak already has a very robust protocol for implementing speech servers. It would be great to implement this for tdsr. some reasons for doing this include:

1. Ability to use the same synths for emacspeak and tdsr.
2. Leveraging existing code for various platforms.
3. Ease of writing new speech synths for both packages.