Allow a list of dicts for row objects

[anselor]

In keeping with tableformatter being able to ingest a diversity of inputs, supporting a dict seems like an obvious use case that's currently missing.

[tleonhardt]

I believe we currently support two use cases related to dictionaries:

• list or another iterable of dicts (dict keys iterated through as rows where each key must be a hashable iterable)
• dict of iterables (keys as columns)

However, we do not generically support dicts. I'm guessing you have a concept for support of a different kind than we currently support?