SAPITTSBackend: convert text to unicode before sending for TTS. Fixes
issues speaking non ascii characters.
Added NVDATTSBackend. This only works on windows. NVDA has to be running.
NVDA controller client library needs to be copied into the lib folder.
Merge branch 'master' of git://github.com/pvagner/service.xbmc.tts into pvagner-master

Conflicts:
	lib/tts.py
	resources/settings.xml