Cleanup/license headers (#1322)

* Attach missing licenses

Attached missing licenses to files that were missing the license
header.

* Apache license additions

Files in examples/lock-app/efr32/ must carry Apache license or a
suitable open source license.

Files in src/app/gen/gen/* are generated; attaching the copyright
notice to those files to satisfy the linter.
diff --git a/.dir-locals.el b/.dir-locals.el
index e16a5aa..d3090a9 100644
--- a/.dir-locals.el
+++ b/.dir-locals.el
@@ -1,3 +1,20 @@
+;;
+;;    Copyright (c) 2020 Project CHIP Authors
+;;    All rights reserved.
+;;
+;;    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.
+;;
+
 ;; Per-directory local variables for GNU Emacs
 ;;  https://www.gnu.org/software/emacs/manual/html_node/emacs/Directory-Variables.html
 ;;