I got a bunch of test failures here:

[ERROR]
Traceback (most recent call last):
Failure: testtools.testresult.real._StringException: ValueError: TestCase.setUp was not called. Have you upcalled all the way up the hierarchy from your setUp? e.g. Call super(HelpCommandTest, self).setUp() from your setUp().


commandant.tests.test_builtins.HelpCommandTest.test_run_commands
commandant.tests.test_builtins.HelpCommandTest.test_run_commands_with_custom_help_help_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_commands_with_custom_help_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_commands_without_docstring
commandant.tests.test_builtins.HelpCommandTest.test_run_hidden_commands
commandant.tests.test_builtins.HelpCommandTest.test_run_hidden_commands_without_hidden_commands
commandant.tests.test_builtins.HelpCommandTest.test_run_many_commands
commandant.tests.test_builtins.HelpCommandTest.test_run_topics
commandant.tests.test_builtins.HelpCommandTest.test_run_topics_ignores_custom_command_help
commandant.tests.test_builtins.HelpCommandTest.test_run_topics_with_custom_help_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_topics_with_custom_underscore_help_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_with_custom_help_text
commandant.tests.test_builtins.HelpCommandTest.test_run_with_custom_help_text_trims_trailing_whitespace
commandant.tests.test_builtins.HelpCommandTest.test_run_with_custom_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_with_custom_topic_strips_whitespace
commandant.tests.test_builtins.HelpCommandTest.test_run_with_hidden_commands
commandant.tests.test_builtins.HelpCommandTest.test_run_with_python_command_topic
commandant.tests.test_builtins.HelpCommandTest.test_run_with_python_command_without_docstring
commandant.tests.test_builtins.HelpCommandTest.test_run_with_stock_help_text
commandant.tests.test_builtins.HelpCommandTest.test_run_with_unknown_command_or_topic_name
===============================================================================
[ERROR]
Traceback (most recent call last):
Failure: testtools.testresult.real._StringException: ValueError: TestCase.setUp was not called. Have you upcalled all the way up the hierarchy from your setUp? e.g. Call super(CommandHelpTopicTest, self).setUp() from your setUp().


commandant.tests.test_help_topics.CommandHelpTopicTest.test_get_help_contents
commandant.tests.test_help_topics.CommandHelpTopicTest.test_instantiate
===============================================================================
[ERROR]
Traceback (most recent call last):
Failure: testtools.testresult.real._StringException: ValueError: TestCase.setUp was not called. Have you upcalled all the way up the hierarchy from your setUp? e.g. Call super(CustomCommandHelpTopicTest, self).setUp() from your setUp().


commandant.tests.test_help_topics.CustomCommandHelpTopicTest.test_get_help_contents
-------------------------------------------------------------------------------
Ran 83 tests in 0.437s

FAILED (errors=23, successes=60)
make: *** [check] Error 1

I've fixed this by adding a new commandant.testing.basic.CommandantTestCase
class that calls the setUp and tearDown methods on both ResourcedTestCase
and TestCase.  The broken test cases now inherit from it, instead of doing
multiple inheritance directly.

Thanks for the cleanups!