Update copyright notice from Swarming to LUCI; add AUTHORS and CONTRIBUTORS.

appengine/components/test_support/test_case.py

-# Copyright 2013 The Swarming Authors. All rights reserved.
+# Copyright 2013 The LUCI Authors. All rights reserved.
 # Use of this source code is governed by the Apache v2.0 license that can be
 # found in the LICENSE file.
 
 import base64
 import contextlib
 import datetime
 import logging
 import time
 import urllib
 
@@ skipping 217 matching lines @@
       yield
     except AssertionError:
       # Assertion can happen if tests are running on GAE < 1.9.31, where
       # endpoints bug still exists (and causes webapp guts to raise assertion).
       # It should be rare (since we are switching to GAE >= 1.9.31), so don't
       # bother to check that assertion was indeed raised. Just skip it if it
       # did.
       pass
     finally:
       self.expected_fail_status = None