Update README.md

README.md

@@ -39,3 +39,23 @@ static void Main(string[] args)
 
 ### Debugging
 Trace errors in your output window, all errors from this library will be captured under the category `Firebase.Notification` for easy debugging.
+
+
+# Licence
+
+```
+Copyright 2018 Frank Odoom
+
+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.
+````
+