Exposing PM and ELK stack ports

Change-Id: I72476acb6edbec2be3a12a08cfa8c3ca2e35d346
Signed-off-by: Eduardo Sousa <esousa@whitestack.com>
diff --git a/installers/docker/osm_metrics/docker-compose.yml b/installers/docker/osm_metrics/docker-compose.yml
index e2ba5c9..f529a01 100644
--- a/installers/docker/osm_metrics/docker-compose.yml
+++ b/installers/docker/osm_metrics/docker-compose.yml
@@ -28,7 +28,7 @@
       - ./datasource-prometheus.yml:/etc/grafana/provisioning/datasources/datasource-prometheus.yml
     hostname: grafana
     ports:
-      - "3000:3000"
+      - "${OSM_PM_PORTS:-3000:3000}"
     networks:
       - netOSM
     depends_on: