Update `test_classification.py`
Update `test_classification.py`

- Update one of the expected values in `test_sparse_predict_sampler()` likely due to the following item in the scikit-learn 0.16 release notes: "RBFSampler with gamma=g formerly approximated rbf_kernel with gamma=g/2.; the definition of gamma is now consistent, which may substantially change your results if you use a fixed value. "
- Fix typo in comment.

ernfrid/skll,ernfrid/skll