TST: Test for MNLogit with strings/factors.
ENH: Make sure MNLogit works with string/factor y
TST: Silence tests.
REF: Refactor for DRY. Handle numpy-like like numpy.
STY: Remove commented code. Pep-8
TST: Fix test for debian failure.
Merge pull request #2048 from jseabold/mnlogit-factor

ENH: MNLogit strings/factor
Merge pull request #2057 from jseabold/fix-arma-failure-debian

TST: Fix test for debian failure.
MAINT: Update folders for build bot
Merge pull request #2060 from jseabold/fix-windows-builds

MAINT: Update folders for build bot
ENH: Make PCA a class and add features

Encompasses all sandbox PCA routines and added features for plotting, selecting
the number of components and rapidly re-projecting on a subset of factors