update database.summarize() and plotting.display_coron_dataset() to support pyKLIP outputs

[mperrin]

• enhance database.summarize function to also look at database.red as well as database.obs, and print a summary of the reduced files.
• enhance display_coron_dataset to know about stage3 files from database.red, and also display those. (Requires some extra steps in the plotting function since the pyklip outputs are organized differently than jwst pipeline outputs, so have to be read in differently.)

The plotting needs some more work and debugging still. But wanted to submit this as a draft for now

[mperrin]

Merged into #84 and further improved there.