CLN: deprivatize factorize_from_iterable
Deprivatize ``_factorize_from_iterable`` and ``_factorize_from_iterables``
pending green, lgtm What is the goal of this? > What is the goal of this?

rule of thumb: respect private naming conventions > What is the goal of this?

This isn't private any more than anything else in ``pd.core``, so just remove the private marker. lgtm. merge master and merge on green.