Add secondary table to hold Data Dictionary

[karenmajewicz]

This proposal is for a simple table to hold the Data Dictionary for datasets. Features:

• CSV import/export
• Editable fields in GBL Admin
• Previewable in GeoBlacklight (as HTML probably)

[karenmajewicz]

I have not decided on the field names yet, but this is an example of a Data Dictionary btaa-6b8461b9-040c-4a7c-b09b-fde0c886c7f2_attribute-definitions.csv

[karenmajewicz]

Here is another. I would make the column headers standardized before upload.btaa-e776f983-39be-4417-81f4-9e91a6501c75.csv