Changes to Issue an OAuth token

the grant_type request property type was generalized from no type to string

removed the required property code from the response with the 400 status

removed the required property detail from the response with the 400 status

removed the optional property context from the response with the 400 status

removed the optional property docs from the response with the 400 status

removed the optional property params from the response with the 400 status

added the non-success response with the status 401

added the required property error to the response with the 400 status

added the required property error_description to the response with the 400 status

api tag auth added