include supplemental_display_text in textToSpeech

[pdtyreus]

Since displayText is initialized to [] the expression !assistResponse.displayText will always be false. This prevents having the textToSpeech array take the value of data.dialog_state_out.supplemental_display_text as desired.

This likely contributes to issue #29

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[pdtyreus]

Sorry for the mess here. I had to amend the author email because of the CLA issue. I have signed the CLA with the email used in the last commit. So I'm just going to leave this alone until I get more guidance.

[Fleker]

Hey @pdtyreus the change looks good, but we'll still require the CLA to be signed, or maybe resigned, before this can be merged.

[pdtyreus]

I had a corporate CLA on file. Just created a personal version also. Maybe that will do the trick.

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[Fleker]

Thanks!