Update roscore to have separate dns and use official ros

Change-Id: Ifb28800bfaba66907ab8178caad5e229d484d848
diff --git a/apps/ros-core/templates/configmap-roscore.yaml b/apps/ros-core/templates/configmap-roscore.yaml
index a2cfa8f..5a7680f 100644
--- a/apps/ros-core/templates/configmap-roscore.yaml
+++ b/apps/ros-core/templates/configmap-roscore.yaml
@@ -12,3 +12,5 @@
 data:
   run_roscore.sh: |
 {{ tuple "bin/_run_roscore.sh.tpl" . | include "ros-core.template" | indent 4 }}
+  net_listener.py: |
+{{ tuple "bin/_net_listener.tpl" . | include "ros-core.template" | indent 4 }}