Authorise endpoint to refresh token

Users of DeltaJSON SaaS service download a refresh token from the DeltaJSON application.

Following end point allows users to pass the existing token and get the new token if the existing one is expired.

Endpoint	https://saas.deltaxml.com/api/json/v1/authorise
Operation	POST
Description	Refresh token for authorisation
Example Request	https://saas.deltaxml.com/api/json/v1/authorise?refresh=REFRESH_TOKEN&expiry=1516239022&id=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
Example Response	JSON `{ "id": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5Mzg5fQ.CT8EItEyc2sih-dgEesJu87fhgJGE85zRYzE6EaCwCA", "refresh": "REFRESH_TOKEN", "expiry": "1516239389" }`
Response Codes	200 OK 500 Server exception