AU Interpretation

[KuroiX]

This is the second step of the input processing pipeline.

The AUs have to be processed to create the input for the Bag of Words algorithm. For now, we just want to extract duchenne smiles.
The current way to find duchenne smiles is: If AU6, use value of AU12. (or the other way round, need to double check with the code)

This can be its own class again, so that different approaches in the future can be exchanged easily.