ENH: Medcouple for robust skewness estimation
ENH: Function allowing other functions to be applied using only 1d
    at a time
ENH: Robust Skewness from Kim and White
ENH: Robust Kurtosis from Kim and White
ENH: Helper functions for quantile.  Different from numpy.
ENH: Tests for medcouple
BUG: Made use of np.apply_along_axis and replaced custom version
General improvements to robust skewness and kurtosis
ENH: Generalized other texts to work along axis for standards
Simplified code to remove new weighted quantile function, instead
    use np.percentile
Removed incorrect test file in tools/tests/test_statstools.py
Added tests for multi-axis functions in stattools
Clean-up and documentation for robust skewness and kurtosis measures
Cleaned-up stattools
Added docstring for those missing
Added test for robust kurtosis
Fixed defect where ties were not handled correctly by medcouple
Reverted space additions around ** operator
Removed unnecessary float powers
100% test coverage

Conflicts:
	statsmodels/stats/tests/test_statstools.py
Revert auto-spacing
ENH: Added flag to select excess or not
Allows raw values to be returned when excess=False

Conflicts:
	statsmodels/stats/stattools.py
Added test for excess=False case

Conflicts:
	statsmodels/stats/tests/test_statstools.py
Vectorized np.percentil use
Switched to vectorized use of np.percentile where appropriate
Cleaned up some excessively verbose code

Conflicts:
	statsmodels/stats/stattools.py
Documentation improvements and additional options
Added math to robust_kurtosis
Added math to robust_skewness
Made some of the parameters in robust_kurtosis settable
Added tests of new features

Conflicts:
	statsmodels/stats/stattools.py
Improved documentation of robust kurtosis
Separated the expected kurtotis calculation

Conflicts:
	statsmodels/stats/stattools.py
Added a release note.
Fixed rebase issues
Fixed spacing with **
Merge pull request #1234 from bashtage/medcouple

ENH: Robust skewness, kurtosis and medcouple measures
CLN: Refactored so that there is no longer a need for 2to3

The codebase has been refactored so that it can exist in a single, unified base.
The strategy closely followed six and pandas.compat, but does not involve any further
dependencies.

The compatability location has been renamed form compatnp, which housed compatnp.py3k, to
just compat, and the main py3k compatability files are in __init__.py so that they can
be directly accessed

Conflicts:
	statsmodels/genmod/tests/test_gee.py
	statsmodels/nonparametric/tests/test_kernels.py
	statsmodels/sandbox/regression/tests/test_gmm.py
	statsmodels/tools/parallel.py
	statsmodels/tsa/vector_ar/tests/test_var.py

Conflicts:
	statsmodels/base/data.py
	statsmodels/tools/decorators.py

Conflicts:
	statsmodels/base/model.py
	statsmodels/compatnp/py3k.py

Conflicts:
	statsmodels/base/model.py
	statsmodels/genmod/generalized_linear_model.py

Conflicts:
	statsmodels/tools/catadd.py

Conflicts:
	statsmodels/base/model.py
	statsmodels/sandbox/regression/tests/test_gmm_poisson.py
	statsmodels/sandbox/stats/multicomp.py
Rolled back absolute imports in api.py