Fix travis kyaml exit and targets

- properly exit non-0 if there are any uncommitted files
- make functions/examples targes
- add missing licenses
- refactor into loop

travis/consider-early-travis-exit.sh

@@ -1,3 +1,6 @@
+# Copyright 2019 The Kubernetes Authors.
+# SPDX-License-Identifier: Apache-2.0
+
 # Exits with status 0 if it can be determined that the
 # current PR should not trigger all travis checks.
 #