Add test for PatchExtractor (float value for max_patches)
Fix float value support for max_patches in PatchExtractor
COSMIT: better notation in CountVectorizer.
COSMIT: same changes in transform method.
COSMIT: more robust condition in inverse_transform.

We need to support other formats than CSC and COO. Besides, tocsr()
doesn't trigger a copy if the matrix is already CSR.
FIX typo in test for RdigeCV
ENH Use csr_matrix.sum_duplicates instead of tocoo
Import gzip and bz2 only if necessary.
DOC typo in RandomizedSearchCV docstring
DOC small typographical fixes in grid_search documentation
COSMIT refactor roc_curve and precision_recall_curve
FIX bug where hinge_loss(..., neg_label=1) produced incorrect results
MAINT: refactored metrics.auc to use np.trapz
Merge pull request #1880 from NicolasTr/patch_extractor_float_max_patches

Support float values for max_patches in PatchExtractor.transform
Fixed precompute issue (again) in ElasticNet and enet_path

The previous fix (https://github.com/scikit-learn/scikit-learn/commit/41ae851643625a2dc933fd0864a20bbd23a4e8cb) didn't change things (https://github.com/scikit-learn/scikit-learn/issues/1734) in the n_samples <= n_features case, as the value of precompute was unchanged and remained truthy.

Also, the same issue existed in enet_path, so I applied the same fix.
Fix setup.py to resolve numpy requirement
during pre-install. This should allow
'pip install numpy cython scipy scikit-learn'
to install scikit.

This fix is based of issue and fixes in Scipy:
https://github.com/scipy/scipy/pull/453
https://github.com/branden/scipy/commit/ad0dd3e883ca5b241dda6136eee921eb900077a0
ENH: add pre_dispatch option to cross_val_score
DOC Fix estimator unsupervised fit method signature

The previous version had repeated the same signature twice instead of describing the supervised and unsupervised cases.
maintenance scripts added for machine learning maps - needed for modifying the map in future
DOC rename lambda to alpha in plot_lasso_coordinate_descent_path. (Re)-Closes #903.