Develop protocol for collection summary outputs

[tyt3]

Add summary of the collection and the items (yaml, readme?) as outputs for the Python scripts

[tyt3]

#metadata.yml
## for archival ... ead, mods to yaml
## for a monograph collection, every marc in the folder (write an empty yaml with one field for "description")
## for archival collections, put series.csv yaml? 
## for series? Need to finish base layer