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
P3K all of feature_extraction passes tests on Py2 and 3
DOC clarify column ordering in SVC scores

http://stackoverflow.com/q/15324593/166749
DOC fixing some more rst / sphinx errors :-/
DOC more sphinx stuff.
FIX: X was converted twice.
COSMIT DictVectorizer.inverse_transform readability
fix the kwarg name
updated the .c file
remade the cython with 0.18
Merge pull request #1767 from rmcgibbo/balltree_docstring

Small Fix: Balltree Docstring Example Has Wrong Keyword Arg
DOC CountVectorizer does NOT do stopword filtering by default
ENH allow SelectKBest to select all features in a parameter search
ENH don't recompute distances in MBKMeans

Previous code not only redid computations, but used 2 * n_clusters * batchsize
space to do it, orders of magnitude more than is required in the sparse case.

Fixes #1765.
ENH cut MiniBatchKMeans memory usage in half for large n_clusters

Also, changed logging message to reflect the (public) class that is logging,
not the (private) function.

New Cython code lives in utils.sparsefuncs, because it may prove more
generally useful.