PERF: made constructions of SparseFrame have less redundant steps

PERF: minor series perf improvement

TST: trying to fix how_lambda in tseries/resample

     PTF

PERF: addtl groupby multi_python perf improvements

PERF: speeds up for Series.__getitem__

PERF: some perf on groupby.....

      added _block, _values in SingleBlockManager

PERF: more reducer improvements

BUG: fixed SeriesBinGrouper hopefully
COMPAT: py3 compat fixes

TST: recover pickles in a particular order or names
TST: stats.tests.test_ols/test_wls is not testing for the correct version

     of statsmodels (fails on 32-bit)

     PTF

TST: make sure to skip the test_wls if our version isn't enough