ENH: Bump Python and NumPy versions. Remove 2.5 only code.
Merge pull request #1020 from jseabold/maintenance/0.5.x

ENH: Bump Python and NumPy versions. Remove 2.5 only code.
BUG: robust.norms.TrimmedMean fix typos in psi_deriv closes #425
Merge pull request #1023 from jseabold/maintenance/0.5.x

BUG: robust.norms.TrimmedMean fix typos in psi_deriv closes #425
BUG: Check for 0 variance not unit. Closes #1025.
TST: Add regression test for #1025.
Merge pull request #1027 from jseabold/maintenance/0.5.x

BUG: Check for 0 variance not unit. Closes #1025.
BUG: return only yfitted if return_sorted is False closes #922
BUG: acorr_breush_godfrey fix nlags choice closes #676
add explicit shapes to TestTransf2: fixes the fail w/scipy PR/2588
REF: add shapes to Transf_gen, small cleanups
DOC: fix docstrings so Latex finishes
Merge pull request #1034 from josef-pkt/distr_args

Fix TransfTwo_gen and ExpTransf_gen distribution classes.
TST: Test for issue 1038.
BUG: Handle non-string names in lag name making.
BUG: Fail gracefully when not enough obs given for order.
TST: Make test compatible with pandas 0.7.x
Merge pull request #1039 from jseabold/fix-arima-int-name

BUG: Fix ARIMA bugs for small data and data with integer names. Closes #1038.
Merge pull request #1035 from josef-pkt/doc_fix_pdf_maint

DOC: fix docstrings so Latex finishes
Merge pull request #1031 from josef-pkt/bug_lowess_oth_maint

BUG: Fix lowess returns and Breusch Godfrey undefined variable.