chore: Update NOTICE.txt with Apache License information

NOTICE.txt

@@ -0,0 +1,11 @@
+This project includes code from the Apache-licensed project erela.js
+
+Portions of this software are licensed under the Apache License, Version 2.0 (the "Apache License");
+you may not use this file except in compliance with the Apache License. You may obtain a copy of the
+Apache License at http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software distributed under the Apache License
+is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the Apache License for the specific language governing permissions and limitations under the Apache License.
+
+Copyright 2021 MenuDocs