Add licensing info in source file.

[H102 H103] Source code should be licensed under the Apache 2.0 license.
All source files should have the licensing header.

Change-Id: I4f9ead44b5efa3616086f5a62a2e0e68854baf44

sahara_dashboard/api/__init__.py

@@ -1,3 +1,16 @@
+# 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.
+
 from sahara_dashboard.api import sahara
 
 __all__ = [