@Carreau is this okay with you?  I agree with @minrk, `HasDisplayData` is a better name.

@minrk atm it's referenced in datatypefilter.py (filter) and extractfigure.py (transformer)...  I can either change the filter & transformer base classes to inherit from `HasDisplayData` or use the python multiple inheritance "feature" to inherit from both.  Do you know if the traitlet architecture is designed to be aware of multiple inheritance?  It may fail since `HasDisplayData` and `ConfigurableTransformer` both inherit from `Configurable`...