SOSA specification examples: Observation Collections

Examples from the SOSA/SSN specification whose root resource is a observation collections resource. Each Turtle example is validated against the SHACL rules of ogc.sosa.properties.observationCollection, and converted to JSON-LD by the ttl-to-jsonld transform, whose output is validated against the ogc.sosa.properties.observationCollection building block (JSON Schema, JSON-LD context and SHACL).