Enable updated JWTs to be sent to extend the exp (Expiry) time

It would be useful to be able to extend the exp value in the JWT so this can be increased as a user continues to work within the application (I'm thinking of WebCore apps in particular).

Obviously this will need to be done on the server and then returned as part of any response. This could be a header field and TSphinxLogin have a OnCheckForNewJWT method.