Merge pull request #48 from NHSDigital/dev/NPA-1711_add_format_to_sea…

…rch_params

NPA-1711: API Update

* Changes structure of RelatedPerson component to match Patient component stucture.
* Updates description to meet APIM requirements
* Specifies identifier and patientIdentifier parameters to have format of token
* Specifies format of Correlation ID
* Changes 200 response descriptions
* Adds Additional FHIR attributes to FHIR components
* Set placeholder version number
* Added instructions for Sandbox Test Scenarios
* Added detail to FHIR bundle link array attribute description