Merge branch 'release/0.24.0' into develop
Update documentation in skll.utilities.generate_predictions
SGDClassifier and Regressor added.
Conventions of PEP8 solved

and added the Rescaled SGDRegressor
RescaledSGDRegressor  and SGDRegressor unit test added
SGDClassifier unit test added
SGDClassifier unit test corrected
SGDClassifier now supports Probability
Merge pull request #118 from nineil/feature/add_sgd

Add SGD
Some initial changes to work with FeatureHasher
Some initial changes to work with FeatureHasher
Some initial changes to work with FeatureHasher
Some initial changes to work with FeatureHasher
FeatureHasher Added
PEP8 verified. No change in learner.py
Updated with hasher_features
Some initial changes to work with FeatureHasher
function _features_for_iter_type_partial erased and changed parameter nro_features of _features_for_iter_type to num_features
All corrections done. Still working in the test files for feature_hasher.
Test files for feature_hasher added.