Add license notice to salt completion

completion/available/salt.completion.bash

@@ -1,3 +1,18 @@
+# Licensed under the Apache License, Version 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.
+
+# Copyright (c) 2020 SaltStack Team
+
+# Original Author:
 # written by David Pravec
 #   - feel free to /msg alekibango on IRC if you want to talk about this file