NGSI-LD Batch Operations - OAS 1.6.1

Show the @context field on top of the Query example and on top of the Batch Post Query response body example (LD+JSON)

Remove unneeded "allOf" statements in the schema definitions of the request body of batch entity operations

The content is an array of strings and it is not supposed to contain the @context field anywhere

Refactor example of response body in Batch Entity Update and capitalize a letter in the summary of Batch Entity Delete

In CIM 6.3.6 HTTP response common requirements it is stated that the provided "Accept header" is ignored when there is an error. Not much is said about multi-status (207), but we can safely say that the responses should be application/json as the @context is present in the request. Definitely no geo resourse is returned in multi-status responses

The previous body contained an array of entities and the @context, instead of having an array of Entities with dedicated @context fields

Adding a folder for defining examples of custom OpenAPI schemas that are compliant with the NGSI-LD OAS.

Eliminate the required option within the Subcription.Periodic schema for fields entities and timeInterval. Move the required option for the entities fields to the schemas statement of the Subscription request body.

Fixing an indentation issue with the additionalProperties field in the Schemas of Entity and Relationship within the NGSI-LD OAS.

Update links within the README file and add a link to view the original NGSI-LD OAS in the Swagger Editor of ETSI Forge.

Create an initial fork repository to work on the OpenAPI Specification (OAS) for the NGSI-LD API specified by the cross-cutting Context Information Management (CIM) ETSI Industry Specification Group (ISG).