COSMIT refactor cross-validation strategies
Include LeavePLabelOut in refactoring
A further refactor
COSMIT Base class for KFold/StratifiedKFold validation
COSMIT make BaseKFold abstract
COSMIT Base class for [Stratified]ShuffleSplit
COSMIT make helpers private with underscore
COSMIT make BaseKFold private with underscore
TST additional tests for preprocessing.Binarizer
Merge pull request #2055 from jnothman/cv_refactor

[MRG] refactor partitioning cross-validation strategies
Merge pull request #2067 from jnothman/test_binarizer

TST additional tests for preprocessing.Binarizer
COSMIT add underscore prefixes where forgotten in cross_validation
Fix wrong argument name in RFECV docstring
Merge pull request #2071 from djv/patch-1

Fix wrong argument name in RFECV docstring
COSMIT much simpler agglomeration inverse_transform
TST stronger test for agglomeration transforms
Merge pull request #2075 from jnothman/agglomeration_simplify

COSMIT much simpler agglomeration inverse_transform
FIX : use unique from fixes
DOC minor fixes to Ward docstrings
DOC fix docstrings for AgglomerationTransform