COSMIT get rid of undocumented attributes on SVMs

sparse was superseded by _sparse; renamed impl to _impl.
PEP8 and allow non-bool truth values in CD
BUG + ENH: removal of components in kernel PCA
Merge pull request #1758 from larsmans/kernelpca-fix

MRG removal of components in kernel PCA
DOC some sphinx / rst fixes
MISC minor fixes in examples
DOC FIX column span alignment problem in NMF ^^
P3K make feature_extraction.text work

All tests pass with Py2 and Py3.
ENH - 3x speedup in the isotonic regression
Fix comment: returns fbeta_score, not f1_score
BUG failing doctest

My laptop didn't catch this, so the explicit np.int64 is probably a good idea.
COSMIT typo
DOC IsotonicRegression wasn't in the changelog at all