removed obsolete options in tts() args
removed obsolete options in tts() args

* removed options in tts() options arguments:
  * splitter (Function), split (Boolean), forceSingleSentence (Boolean)
* removed defaultSplitter implementation
* FIX for onReadyCallback in single-senctence mode: invoke callback with
correct arguments
* allow setting log-level via configuration
mmig/mmir-lib