New qpid-dispatch-console provides a different httpRootDir than default root directory used by qpid-dispath-router

New version of qpid-dispatch-router uses "/usr/share/qpid-dispatch/console/stand-alone" as the default httpRootDir. But when installing new qpid-dispatch-console package, the pages are available at "/usr/share/qpid-dispatch/console".

We must define httpRootDir on the listener to bypass this issue.