- feat: introduce new feature names `ml_score_???` where `?`
can be a digit or a lower-case letter of the alphabet (77)
- feat: introduce new functions `dclab.definitions.feature_exists`
and `dclab.definitions.scalar_feature_exists` for checking the
existence of features (including the `ml_score_???` features
which are not in `dclab.definitions.feature_names`)
- feat: introduce ancillary feature `ml_class` which is
defined by the `ml_score_???` features
- enh: fmt_dict automatically converts scalar features to arrays
- ref: replace check for `dclab.definitions.feature_names`
by `dclab.definitions.feature_exists` where applicable
- ref: replace access of `dclab.definitions.feature_name2label`
by `dclab.definitions.get_feature_label` where applicable
- ref: do not automatically fill up all the box filtering ranges
in `RTDCBase.config["filtering"]` with zeros; raise ValueError
if user forgets to set both ranges
- docs: major revision (promote Shape-Out 2 and DCOR)