Echo "DATABASE IS READY TO USE!" when ready

This message is the same as what Oracle's image displays, allowing other programs that look for this message to find it making this image compatible with Oracle's.

Author: candrews

assets/startup.sh

@@ -38,3 +38,7 @@ for f in /docker-entrypoint-initdb.d/*; do
   esac
   echo
 done
+
+echo "#########################"
+echo "DATABASE IS READY TO USE!"
+echo "#########################"