Babbler: passing xAAL notifications (attributes_change) to the espeak TTS.

Depends on libxaal
and on debian packages: libespeak-dev mbrola mbrola-en1 mbrola-fr1

Note: TTS parameters are hardcoded... Use gespeak to try others.

A kind of multilingual support is provided using gettext&co.
For now this includes english and french.
(Configure your LC_MESSAGES environment variable.)

Dedicated sentences are proposed for lamps and thermometers devices.
Other devices are announced with a kind of generic sentence template...

Metatdata DBs are query for words to tell in association to devices
(recorded with the key "tts")