Add TFSpeech2Text
# 🚀 Feature request
Add TensorFlow implementation of Speech2Text model.

## Your contribution

I'll try to do this.

**Reviewers:** @patil-suraj 
Is this still in progress? I didn't see a WIP PR, but I'd like to use the TensorFlow version if possible.<|||||>Hello @will-rice, I have this in progress. I'll try to finish some missing components tomorrow and then open the PR for a review :)<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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