data/ml/README.md passextract: Few feature ideas
CanByPassage: Remove, dead code from the very early days
Introduce AnswerFeature, AnswerFV; use instead of FS attributes

Answer scoring should still yield the exact same values.

We are performing scoring at the wrong moment, soon we will tweak it to happen after the CAS merger.
AnswerFV: When merging FVs, by default take max() of feature values instead of dropping them