Normalize the hypothesis based on the reference text

[NickRuiz]

Normally in ASR evaluations, adjudication is used to avoid penalizing minor orthographic differences between the reference and the hypothesis. While this is often down with an outside normalization file (like a GLM file in the NIST evaluations), we really want to "modify" the hypothesis to look like the reference for the sake of scoring and alignment. The hypothesis should remain as-is, but the tool should be configurable to penalize or permit minor orthographic variations -- but in all cases the alignments should be correct.

Examples:

• Contractions: isn't => is not
• Numbers: 50 => fifty
• UK to US English: favour => favor

This enhancement exists in the private repository but needs to be refactored and to the public repo.

[NickRuiz]

Pushed code that handles contractions and numbers. Not UK -> US English yet. Will integrate into power.py soon.