added unit test for null spectrum approximation in quadratic time mmd and a minor spell correction
Merge pull request #2087 from lambday/develop

added unit test for null spectrum approximation in quadratic time mmd and a minor spell correction
Made CLinearOperator generic
Refactor MulticlassMultipleOutputLabels
Added back the commented code.
Removed old enumerator
Fixed whitespaces and Documentation
Merge pull request #2088 from Jiaolong/refactor_MulticlassMultipleOutputLabels

Remove MulticlassMultipleOutputLabels
Renamed apply_multiclass_multiple_output to apply_multilabel_output
Renamed python example classifier_multiclassmultipleoutputlinlinear_modular.py
Decision Tree Notebook started
Merge pull request #2096 from Jiaolong/refactor_MulticlassMultipleOutputLabels

Renamed apply_multiclass_multiple_output - Thanks for fixing!
typos fixed, final exercise plot fixed
minor change in last code snippet
Merge pull request #2097 from mazumdarparijat/pca

Decision Tree Notebook started
data submodule updated
NEWS update
Merge pull request #2099 from mazumdarparijat/pca

data submodule update and NEWS update
Added multilabel reader in LibSVMFile.
Added multilabel writer in LibSVMFile. Updated LibSVMFile unit test.