DOC: bootstrap=True by default
ENH reduce memory overhead of storing tree ensemble
Merge pull request #2438 from arjoly/tree-mem-overhead2

[MRG] ENH reduce memory overhead of storing tree ensemble
Update what's new
MAINT Update six to version 1.4.1

Fixes #2434.
DOC output types should never be "array_like"

We document *exactly* what we give back. "array_like" is the NumPy
way of saying "anything goes that passes np.asarray".
DOC+COSMIT: typos, lots of them

Fixes #2102. There's one typo left in joblib which is better fixed
upstream.
ENH: don't call astype when a copy is not needed

See #2206. This doesn't fix all of the cases.
BUG oops, *safe_* asarray
Merge branch 'master' of github.com:scikit-learn/scikit-learn into tree-shuffle

Conflicts:
	sklearn/tree/_tree.c