make gm self-tests launch python unittests automatically

gm/rebaseline_server/test_all.py

 #!/usr/bin/python
 
 """
 Copyright 2014 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 Run all unittests within this directory tree, recursing into subdirectories.
-
-TODO(epoger): Launch this automatically on the housekeeper bot, but first make
-sure it works properly after having been checked out (from both git and svn)
 """
 
 import os
 import unittest
 
 
 def main():
   suite = unittest.TestLoader().discover(os.path.dirname(__file__),
                                          pattern='*_test.py')
   results = unittest.TextTestRunner(verbosity=2).run(suite)
   print repr(results)
   if not results.wasSuccessful():
     raise Exception('failed one or more unittests')
 
 if __name__ == '__main__':
   main()