Add metadata URL to representations of entity references, define format for collections of references

Protocol: adapt metadata URL pattern for entity references: no need for prefixing the reference with an entity set, just use $metadata#$ref and $metadata#$ref/@Element. Atom: add metadata:metadata attribute to metadata:ref element. Require it in single reference and in collection of entity references. JSON: define odata.metadata name/value pair for entity references, use odata.id instead of odata.ref, define format for collection. Example for single reference { "odata.metadata": "http://host/service/$metadata#$ref/@Element", "odata.id": "Orders(10643)" } Example for collection of references { "odata.metadata": "http://host/service/$metadata#$ref", "value": [ {"odata.id":""} ,...] } Accepted: https://www.oasis-open.org/committees/download.php/49375/odata-meeting-39_on-20130530-minutes.html#odata-422

https://www.oasis-open.org/committees/download.php/49405/odata-v4.0-wd02-part1-protocol-2013-06-04.docx https://www.oasis-open.org/committees/download.php/49403/odata-atom-format-v4.0-wd02-2013-06-04.docx https://tools.oasis-open.org/version-control/browse/wsvn/odata/trunk/spec/schemas/metadata.xsd?rev=325 https://www.oasis-open.org/committees/download.php/49404/odata-json-format-v4.0-wd02-2013-06-04.docx Accepted: https://www.oasis-open.org/committees/download.php/49557/odata-meeting-41_on-20130613_14-F2F-minutes.html#odata-422