Uninstall node_exporter when removing OSM stack

Change-Id: I71680b2924e307738742efb69173c883662a605a
Signed-off-by: lavado <glavado@whitestack.com>
diff --git a/installers/full_install_osm.sh b/installers/full_install_osm.sh
index 777c855..0bf2e20 100755
--- a/installers/full_install_osm.sh
+++ b/installers/full_install_osm.sh
@@ -194,6 +194,7 @@
         else
             remove_stack $OSM_STACK_NAME
             remove_stack osm_elk
+            uninstall_prometheus_nodeexporter
         fi
         echo "Now osm docker images and volumes will be deleted"
         newgrp docker << EONG
@@ -615,6 +616,16 @@
     return 0
 }
 
+function uninstall_prometheus_nodeexporter(){
+    sudo systemctl stop node_exporter
+    sudo systemctl disable node_exporter
+    sudo rm /etc/systemd/system/node_exporter.service
+    sudo systemctl daemon-reload
+    sudo userdel node_exporter
+    sudo rm /usr/local/bin/node_exporter
+    return 0
+}
+
 function install_from_lxdimages(){
     LXD_RELEASE=${RELEASE#"-R "}
     if [ -n "$LXD_REPOSITORY_PATH" ]; then