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
Add what's new entry for pairwise_distances_argmin_min.
DOC improve encoding docs
removing NWS from list of stock prices
MAINT remove deprecated code from CD
FIX finish deprecation of indices in CV

* default None value so explicit True/False can be detected
* remove doc for deprecated indices parameter
* indices property with DeprecationWarning

Fixes #2436.
Partially revert "MAINT remove deprecated code from CD"

This reverts commit 680234d3687c22023d99a439ee832d9d33136c9d.

The dictionary learning code seems to rely on coef_init (even
though CD docstrings say it's a no-op). I leave it to @vene and
@agramfort to sort this out further.
FIX issue #1993: passing a multilabel indicator is no more noop
TST speed up biclustering tests

They were taking 7s to run, down to 3.6s.
MAINT remove dead code from LibSVM
FIX : get rid of coef_init in Lasso in dict learning