Update to accept fully tagged input

[TheresaSchmidt]

The alignment model currently expects tagged data with labels O and A. Update so the model will also accept the full range of labels generated by the tagger, i.e. interpreting all labels starting with A as action labels and all other labels as irrelevant for the alignment task.

[TheresaSchmidt]

Also, the tagger generates BIOUL tags and the alignment model seems to expect IOB2.

[siyutao]

the tagger generates BIOUL tags

For consistency, I've updated the tagger to output IOB2 directly, so there's no need to update the model in that respect. Thanks!

[TheresaSchmidt]

i.e. interpreting all labels starting with A as action labels and all other labels as irrelevant for the alignment task.

Actually, we want the alignment model to distinguish between the different action types.