Collapsed all specified_cv_folds tests into a single function
Collapsed all specified_cv_folds tests into a single function

- Modified make_cv_folds_data to use fewer examples otherwise the test takes too long when using RBFSampler.
- Collapsed all specified_cv_folds tests with/without feature-hashing and with/without sampling into a single function.

ernfrid/skll,ernfrid/skll