Share the Web Serve with another Application

Recent effort to put Keystone into the HTTPD container was stymied by the fact that THe Horizon DJango Dashboard owns all of the URLs in the HTTPD container. Since DJango allows for the end user to inject whatever they want as peers to /project or /auth, there is the possibility that an end deployer has created a Keystone UI dashboard. TO deconflict, the dashboard should be pushed one level down the URL stack, so that instead of http://hostname/auth the login suburl would be http://hostname/dashboard/auth . And so on. The code change to make this happen is relatively minor, but the testing and integration steps are somewhat more fragile and complex.