Split generic subcommand code off its own module.

tests/git_cl_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Unit tests for git_cl.py."""
 
 import os
 import StringIO
 import stat
 import sys
 import unittest
 
 sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 
 from testing_support.auto_stub import TestCase
 
 import git_cl
 import subprocess2
 
+# Make submodule be able to find the commands.
+git_cl.subcommand.MAIN_MODULE = git_cl
+
 
 class PresubmitMock(object):
   def __init__(self, *args, **kwargs):
     self.reviewers = []
   @staticmethod
   def should_continue():
     return True
 
 
 class RietveldMock(object):
@@ skipping 681 matching lines @@
       obj = git_cl.ChangeDescription(orig)
       obj.update_reviewers(reviewers)
       actual.append(obj.description)
     self.assertEqual(expected, actual)
 
 
 if __name__ == '__main__':
   git_cl.logging.basicConfig(
       level=git_cl.logging.DEBUG if '-v' in sys.argv else git_cl.logging.ERROR)
   unittest.main()