Edit recommendations for KML spatial data files in EML

[gremau]

The Design for Special Cases document currently recommends KML as a file format for spatial data entities. It is common for KML files to contain style information embedded as HTML inside the file, and the EDI portal's EML Congruence Checker throws the urlReturnsData error when it reads data containing HTML from a URL. The solution for this should be to convert the file to KMZ (compressed archive of a KML) and publish that.

This problem happens for KML files described as otherEntities, but it is unclear if this would be a problem for a KML described as a spatialVector entity type.

[srearl]

@gremau - This, among others, is one of the reasons that I default to GeoJSON. I do not experience any congruence issues with that file type. Perhaps consider changing the recommendation from KML to GeoJSON.