train group no longer mandatory in CSVDataset

Closes bob.bio.vein#27

See merge request !303

Support a pipeline with "passthrough" or None as estimator

See merge request !302

Setting an estimator as "passthrough" or None no longer fails.

Fixed issue with score normalization with dev/eval groups

See merge request !301

Remove invalid entry-points from setup.py

See merge request !299

Follow up of !296

See merge request !298

Make PipelineScoreNorm behave like PipelineSimple
Remove dask_score_normalization_pipeline as it was not needed and it was
confusing
Add test cases for pipeline click commands

Fix _data_valid function

Closes #185

See merge request !297

Fixes #185

Changed the API of BioAlgorithm and score post processors

Closes #179

See merge request !296

Changed the API of the BioAlgorithm class

Renamed allow_scoring_with_all_biometric_references
to score_all_vs_all

Changed the API of score post_processors

Update the docs accordingly

Fixes for bob.pipelines changes and docs improvements

Closes #184

See merge request !295