add license notice

scripts/install.sh

@@ -1,3 +1,21 @@
+# 
+# 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.
+# 
+# NOTICE:
+# The following was adapted from the original source, and includes modified changes.
+# Original source: https://github.com/DopplerHQ/cli/blob/08cd5113f646ed98d4ca806c204428c68a69b8a1/scripts/install.sh
+#
+
 #!/usr/bin/env sh
 
 set -e