Added multiple linear Theil-Sen regression
Added an example and documentatin for Theil-Sen
Added subpopulation parameter to Theil-Sen
Added parallelization support to TheilSen Estimator
Improved parallelization for Theilsen estimator
Merge branch 'master' into theilsen
Cleanups and corrections for Theil-Sen regression.
Removed subpopulation=None option in TheilSen
xrange fix for Python3 in TheilSen
FIX Theil-Sen unittest for older Scipy Version

Usage of fmin_bfgs instead of minimize.
FIX that some functions in Theil-Sen were public

- _spatial_median, _breakdown_point and _modweiszfeld_step are now
private as suggested by agramfort.
- moved _lse before TheilSen class.
FIX usage of linalg from Scipy in Theil-Sen

Replaced usage of numpy.linalg by scipy.linalg as suggested by
agramfort.
FIX: Let Theil-Sen handle n_samples < n_features case

Theil-Sen will fall back to Least Squares like if number of samples is
smaller than the number of features.
FIX: Python 2.6 format syntax in Theil-Sen

Fix of "zero length field name in format" ValueError due to Python 2.6
in TheilSen class.
Vectorization of theilsen._modweiszfeld_step

Replaced the for-loop in linear_model.theilsen._modweiszfeld_step by
array operations as suggested by jnothman
FIX: Parallel unittests for Theil-Sen estimator

Instead of testing the various codepaths with n_jobs of joblib, now the
functions _get_n_jobs and _split_indices of the theilsen class are
tested as pointed out by agramfort.
FIX: TheilSen supports old Numpy versions
DOC: Comparison of Theil-Sen and RANSAC

Added a simple case where Theil-Sen apparently outperforms RANSAC.
Some recommendations when to use one over another.
DOC: Fixed typo in Theil-Sen example.
FIX: Some coding style fixes in TheilSen unittest.