MAINT: clean up comments/commented-out code in distributions.py; some PEP8 fixes.
MAINT: enable rdist._cdf, making it a lot faster.  Closes gh-1285.

Issue for hyp2f1 that is worked around is discussed in gh-1561.
ENH: add central moment methods to invweibull and loglaplace distributions.

Faster, more accurate and removes a warning generated by the distribution fit
test for invweibull.
TST: speed up stats tests some more, and add run_module_suite to each test file
Merge pull request #2612 from rgommers/stats-distributions-cleanup

MAINT: clean up comments/commented-out code in distributions.py
Added tests for the mood function, that check generalization to 2d case and effect of changing parameter order
generalize mood function to 2d case
started generalization of mood's test to n-d case, created function mood_nd
add function mood_nd and tests for it
Optimize the code using np.rollaxis (proposed by josef-pkt)
Start correction according to Josef's and Ralph's comments
pep8 and remove temp array as suggested by Ralf(in the discussion)
delete other_axis, since not needed
MAINT: some cleanup of stats.mood docstring and code.

Also return floats instead of 0-D arrays, for backwards compatibility.
TST: consolidate stats.mood tests