Enable UUIDs (used for id for each MD record) to become a valid URI

[njhoebel]

Will want to provide IRI's (=valid URI's) for each MD record in order for MD content in DMTC to be FAIR. Apparently can be done. See the following references:
https://json-schema.org/draft/2019-09/json-schema-validation.html, sections 7.3.5 and 7.3.6

Also, a helpful (?) discussion at: json-schema-org/json-schema-spec#542.

[njhoebel]

Based on discussion, will use the system id field (schema.org/Thing/Identifier) to create a globally unique, persistent ID for each metadata record in the system to meet FAIR requirements (in the form of an IRI ==> a valid URI. Will close this issue and open another one to add a field to the schema for the MD record ID.