If exceptions are thrown during Validate the token is not valid.
The calling IP is actually the API server.  So we need to accept the API as part of the message.  API server will query the IP of it's caller and pass it in.
Remove / cleanup legacy ToString() method.
Add request message for passing data to Token Service validation method.
Add token service proxy for calling token validation method.
Add message handler to perform client request authorization against the token service validation API.
Track newly added files.
Wire up the message handler.
Merge pull request #6 from walterpinson/client-authentication-handler

Client authorization handler