Add support for TTS

[evancohen]

Up for consideration: should we add TTS to Sonus (provide geraric wrappers like we'll do for streaming cloud speech), or does that fall outside of the scope of the module?

[daangemist]

I have started a repo at https://github.com/matueranet/genie-ai that aims to do exactly this. There is nothing to see yet, but it will wrap sonus for stt and provide wrappers for different tts engines. Maybe we can work together? I plan to use the MIT license.

[daangemist]

It will be an autonomous module of a larger project. More details here: https://github.com/matueranet/genie-docs