[mimictts] Initial contribution (#13045)

* [mimictts] Initial contribution

Add a voice service for Mimic (version 3) TTS from Mycroft AI. 

Signed-off-by: Gwendal Roulleau <gwendal.roulleau@gmail.com>

bundles/pom.xml

@@ -410,6 +410,7 @@
     <module>org.openhab.voice.googletts</module>
     <module>org.openhab.voice.mactts</module>
     <module>org.openhab.voice.marytts</module>
+    <module>org.openhab.voice.mimictts</module>
     <module>org.openhab.voice.actiontemplatehli</module>
     <module>org.openhab.voice.picotts</module>
     <module>org.openhab.voice.pollytts</module>