Merge branch 'dask-pipelines' of gitlab.idiap.ch:bob/bob.bio.base into dask-pipelines

bob/bio/base/config/examples/lda_atnt_legacy.py

bob/bio/base/config/examples/pca_atnt.py

bob/bio/base/config/examples/pca_mobio-male.py

...bio/base/pipelines/vanilla_biometrics/abstract_classes.py

bob/bio/base/pipelines/vanilla_biometrics/legacy.py

bob/bio/base/script/vanilla_biometrics.py