[es] Bump to 5.0.1

* explicitly configure default JVM heap size
* /conf needed ownership fixed
For #112

elasticsearch/start

@@ -125,7 +125,7 @@ echo "Starting Elasticsearch with the options $OPTS"
 CMD="$ES_HOME/bin/elasticsearch $OPTS"
 if [ `id -u` = 0 ]; then
   echo "Running as non-root..."
-  chown -R $DEFAULT_ES_USER /data
+  chown -R $DEFAULT_ES_USER /data /conf
   su -c "$CMD" $DEFAULT_ES_USER
 else
   $CMD