Merge remote-tracking branch 'vene/sc' into vene-sc

doc/modules/classes.rst

doc/modules/decomposition.rst

doc/modules/linear_model.rst

examples/decomposition/plot_faces_decomposition.py

examples/decomposition/plot_img_denoising.py

scikits/learn/decomposition/__init__.py

sklearn/decomposition/__init__.py

sklearn/decomposition/dict_learning.py

sklearn/decomposition/sparse_pca.py

sklearn/decomposition/tests/test_dict_learning.py

sklearn/decomposition/tests/test_sparse_pca.py

sklearn/feature_extraction/image.py

sklearn/linear_model/omp.py

sklearn/linear_model/tests/test_omp.py