added missing docker entrypoint

entrypoint.sh

@@ -0,0 +1,19 @@
+#!/bin/sh
+
+# File: entrypoint.sh                                                                    #
+# Author: Rodrigue Chakode <rodrigue.chakode @ gmail dot com>                            #
+#                                                                                        #
+# Copyright © 2019 Rodrigue Chakode and contributors.                                    #
+#                                                                                        #
+# This file is part of hugo-mx-gateway software.                                         #
+#                                                                                        #
+# hugo-mx-gateway is licensed under the Apache License 2.0 (the "License");               #
+# you may not use this file except in compliance with the License. You may obtain        #
+# a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0                   #
+#                                                                                        #
+# Unless required by applicable law or agreed to in writing, software distributed        #
+# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR            #
+# CONDITIONS OF ANY KIND, either express or implied. See the License for the             #
+# specific language governing permissions and limitations under the License.             #
+
+/app/hugo-mx-gateway