Move gold standard example documentation?

[MathewBiddle]

Move the content at https://ioos.github.io/ioos-metadata/gold-standard-examples.html to somewhere at https://ioos.github.io/erddap-gold-standard/

cc: @mwengren

[mwengren]

When this page is moved over, we should also:

• [ ] Improve organization/categorization of dataset 'types' to include - how best to represent the diversity/variety of IOOS' data types and associated 'standard' formats to end users and data managers?
• [ ] Add links to the corresponding .nc file in the repo, as well as the ERDDAP dataset link in the Gold Standard ERDDAP service: https://standards.sensors.ioos.us/erddap/info, in addition to any RA-specific links
• [ ] Add other example datasets (ATN trajectory, ATN profile, what others...?)