Made it so you can now have feature files that do not have labels. The IDs still need to match, but this makes it much less of a pain when generating features separately.
Bumped version to 0.9.5
Added additional check to make sure at least one feature file has classes specified.
Added support for the tsv_label field in experiment configuration files, and we now determine if data is labelled on the fly.
Made tsv_label optional argument for _load_featureset.
Merge pull request #11 from EducationalTestingService/merge_without_labels

Can now include feature files that are missing class labels in with those that have them with run_experiment.