Support for text-to-speech and save/restore state

Hi Jishi,
I have added some basic support for tts (Google translate) and save/restore state in your great module. With these commands you can:

<ol>
<li> Save state </li>
<li> Play tts message </li>
<li> Restore state </li>
</ol>

I have only tested with one Sonos speaker and with streaming radio. I guess it need some more work to be more generic. But I hope this can be a good start.

<b>Tts - say</b>:
 http://localhost:5005/{room name}/<b>say</b>/{text_message}/{language}
where: 
<b>text message</b> is a text string. Spaces must be replaced by %20. Example: Hello%20World
<b>language</b> is the preferred spoken language. Example: en = English, sv = Swedish. Default if not given is English. 

<b>Save state - saveall/restoreall</b>
http://localhost:5005/saveall
http://localhost:5005/restoreall