Bind to any interface, not just localhost

Change-Id: Ifc0d17b9e23d2c850b463ce1714ebed32805fe3f
diff --git a/visualisation/visualisation.py b/visualisation/visualisation.py
index 5df9163..72c5ee7 100644
--- a/visualisation/visualisation.py
+++ b/visualisation/visualisation.py
@@ -75,7 +75,7 @@
                                 filemode = 'a')
             logging.info('%s visualisation starting up', self.state.banner)
 
-        server = VlandHTTPServer(('localhost', self.state.config.visualisation.port),
+        server = VlandHTTPServer(('', self.state.config.visualisation.port),
                                  GetHandler, self.state)
         server.serve_forever()