Reorganize cv tests
Add cv iterators for train/valid/test splits
Add more tests
Update docstrings
Merge in preprocessing stuff
Re-add new dataset iterators
Update docstrings
Fix test imports
Set failed imports = object
Merge branch 'master' of github.com:lisa-lab/pylearn2 into cv_validation_set
Deepcopy Train components instead of Train object
Cleanup variable use
Add TrainCV extensions
Merge pull request #1 from skearnes/cv_save_best

Merge in TrainCV extensions
Cleanup
FAQ section added to docs
Add save_folds to MonitorBasedSaveBestCV
Update doctrings
typo and format cleaning
more line breaks