Add LICENSE

Author: Rishit-dagli

README.md

@@ -89,3 +89,20 @@ git clone [email protected]:Rishit-dagli/Gradient-Centralization-TensorFlow
 pip install -e .[dev]
 ```
 
+## License
+
+```
+Copyright 2020 Rishit Dagli
+
+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.
+```