fix cut-off ML map
Better test for auc_score.
Optim for Crammer-Singer formulation in binary case.
Completely avoid for loop in _auc.
commit added for hack-warning
Merge pull request #2337 from jaquesgrobler/DOC_fix_cut_ML_flowchart

fix cut-off ML map - temporary fix with js hack.. must do a proper css fix. leaving issue open
ENH : simplify ProabilisticPCA covariance_ computation + misc in pca.py
ENH : avoid extra alloc in _infer_dimension_ in pca.py
FIX : self.component in PCA was changed by fit when passed mle or explained variance
ENH : avoid extra allocation in FactorAnalysis
ENH : use math.log and not np.log for scalars
doc fix
misc
FIX : broken fit_transform
Merge pull request #2338 from agramfort/pca_cleanup

PCA cleanup
DOC add link to fetch_covertype to covertype narrative docs
DOC improve docstrings in sklearn.base

These show up on almost all estimators!
Converted Markdown style link to restructured text
Merge pull request #2345 from rgbkrk/patch-1

Converted Markdown style link to restructured text
Typo.