Update assembly_site.md

Expanded description and added references.

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

-- Created metadata for naboreports - md and xml (Hanna and Chris) -- Updated metadata-templates - xlsx, md, and xml (Angie) -- Updated metadata for Cairns NW Iceland - md and xml (Angie) -- Updated metadata for Nabonosead - md and xml (Angie) -- Updated metadata for Paleoclimate - md and xml (Angie) -- Updated metadata for Sagas - md and xml (Angie) -- Updated metadata for Sead - md and xml (Angie) -- Updated metadata for Tephrabase - md and xml (Angie) -- Updated metadata for Whales - md and xml (Angie)

Types of changes

[ ] New dataset
[ ] Fix: Typographical Errors
[ ] Encoding adjustments
[ ] New Field(s) added to each data object
[ ] Remove Field(s) from each data object
[X] Other

Checklist:

[ ] Data is encoded to UTF-8
[ ] Data follows GeoJSON standards
[ ] I have performed a self-review of my own dataset
[ ] I understand I still need to "Process" my data in the main DataARC Contributor Tool

castuofa / dataarc-source