When a data standard/specificaion is used for a given field, provide a way to define _which_ standard was used.

[Cskyleryoung]

For example, if the ITU-T E.123 standard is used to define email and url in an instance of the service table, how can we specify or define which standard was used? It would be extremely helpful for parties ingesting the data to know IF a standard is used for certain fields, and if so, WHICH one.

One option would be to use meta data about fields and tables. Another might be to introduce a concept of profiles that define this kind of information about a given instance of HSDS, maybe as JSON or a separate table (going back to meta data).

I think we should only support existing standards (like ANSI or ITU-T) that are something we can link to for documentation, as opposed to ad-hoc or "on the fly" standards for fields.

Nudging @greggish and @robredpath to contribute comments on this.