Need CCPP scheme description metadata

As CCPP-ized physics and chemistry schemes are shared amongst host models, it may become important to include additional metadata somewhere in the scheme comments that can help users know the current development state and provenance of the scheme itself. So far we have come up with the following list of information that would be good to have for each scheme, if possible:

- The institution/lab that provided the scheme.
- A scheme reference URL (e.g. a DOI to a paper, or a URL to website documentation).
- A scheme description summary (e.g. a few sentences on what the scheme is doing and/or what is for).
- The last modification date.
- Contact person (e.g. name and email).

This is in no way an exhaustive list, and we can always separate "mandatory" versus "encouraged" metadata. If anyone has additional description metadata they would like to add, or have strong feelings on what should be required versus just recommended, then please feel free to add a comment here.

Hopefully this issue will be closed once all of the schemes that currently exist in this repo have been updated with at least the minimum set of description metadata that folks have decided should be mandatory.