Pass a phoneme callback to NSSpeechSynthesizer

[TheQuinbox]

When using this module with NSSpeechSynthesizer, STDERR gets spammed with the following:

NSSpeechSynthesizer: [NSSpeechSynthesizer _setupCallbacks] - NSSpeechSynthesizer: Error setting soPhonemeCallBack

I bleieve the syntax of the function you want is:

function speechSynthesizer_willSpeakPhoneme_(synth, phoneme)
  return
end

This fixed it in a Python project, at least.