OAuth 2 refresh token support

The OAuthHandler class does not provide any option to expire the underlying Cookie ticket upon expiry of the Bearer Token, also it does not have any support for Refresh tokens other than storing the value in AuthenticationProperties.

I Suggest the following:
Add a property: bool ExpireUponTokenExpiry to RemoteAuthenticationOptions

On authenticating ticket, check this property
if false just return AuthenticateResult.Success upon validating the ticket
if true and bearer token is not expired return AuthenticateResult.Success
if true and bearer token is expired
-> if refresh_token isSet in AuthenticationProperties, Exhange the refresh token for new bearer token through http backchannel,
-> if no refresh_token is set, start a new OAuth authentication flow, with RedirectResult