Merge branch 'multi_channel_preproc' into 'master'

bob/pad/face/config/database/__init__.py

bob/pad/face/config/database/batl/__init__.py

bob/pad/face/config/database/batl/batl_db.py

bob/pad/face/config/database/batl/batl_db_depth.py

bob/pad/face/config/database/batl/batl_db_infrared.py

...d/face/config/database/batl/batl_db_rgb_ir_d_grandtest.py

bob/pad/face/config/database/batl/batl_db_thermal.py

.../config/preprocessor/video_face_crop_align_block_patch.py

bob/pad/face/preprocessor/VideoFaceCropAlignBlockPatch.py

bob/pad/face/test/test.py

doc/mc_autoencoder_pad.rst

setup.py