Adds the ability to shutdown main router thread via an HTTP request. Don't forget to setup security for this interceptor.
Has undefined behavior when Membrane is not started from command line (=via the RouterCLI class, which <tt>membrane.cmd</tt>/<tt>membrane.sh</tt> do use).
Only actually terminates the running JVM, when used in the first <tt><router></tt> bean (which implicitly stands for <tt><router id="router"></tt>) called "router".