The output directories for the target under test may differ when the target is under a config transition (config_settings is passed to analysistest.make). Since analysis tests may assert about the command-line of generated actions, and those command-lines may contain paths to output files, this is useful information to expose.
* Fix a number of misc issues to allow google usage of bazel-skylib
1. Missing copyright header
2. Shell test fixes to use TEST_TMPDIR to have write access to directories
3. diff_test fix to use TEST_SRCDIR
* added a comment as to why diff_test_tests is local
* ran buildifier
Christopher Parsons