publish revocation endpoint, addresses #520

openid-connect-server/src/main/java/org/mitre/discovery/web/DiscoveryEndpoint.java

@@ -306,6 +306,7 @@ public class DiscoveryEndpoint {
 		m.put("op_tos_uri", baseUrl + "about");
 
 		m.put("introspection_endpoint", baseUrl + "introspect"); // token introspection endpoint for verifying tokens
+		m.put("revocation_endpoint", baseUrl + "revoke"); // token revocation endpoint
 		
 		model.addAttribute("entity", m);