pylint: Update pylint to 1.7.1, run on tests/ and tools and fix complaints.

The motivation for this is that
 a.) 1.7.1 runs with python 3.6 (bionic)
 b.) we want to run pylint on tests/ and tools for the same reasons
     that we want to run it on cloudinit/

The changes are described below.
- Update tox.ini to invoke pylint v1.7.1.
- Modify .pylintrc generated-members ignore mocked object members (m_.*)
- Replace "dangerous" params defaulting to {}
- Fix up cloud_tests use of platforms
- Cast some instance objects to with dict()
- Handle python2.7 vs 3+ ConfigParser use of readfp (deprecated)
- Update use of assertEqual(<boolean>, value) to assert<Boolean>(value)
- replace depricated assertRegexp -> assertRegex
- Remove useless test-class calls to super class
- Assign class property accessors a result and use it
- Fix missing class member in CepkoResultTests
- Fix Cheetah test import

2 files changed, 3 insertions, 2 deletions

diff --git a/tests/cloud_tests/testcases/base.py b/tests/cloud_tests/testcases/base.py
index 1706f59b..1c5b5405 100644
--- a/tests/cloud_tests/testcases/base.py
+++ b/tests/cloud_tests/testcases/base.py
@@ -12,7 +12,8 @@ from cloudinit import util as c_util
 class CloudTestCase(unittest.TestCase):
     """Base test class for verifiers."""
 
-    data = None
+    # data gets populated in get_suite.setUpClass
+    data = {}
     conf = None
     _cloud_config = None
 
diff --git a/tests/cloud_tests/testcases/modules/set_hostname_fqdn.py b/tests/cloud_tests/testcases/modules/set_hostname_fqdn.py
index eb6f0650..a405b30b 100644
--- a/tests/cloud_tests/testcases/modules/set_hostname_fqdn.py
+++ b/tests/cloud_tests/testcases/modules/set_hostname_fqdn.py
@@ -1,7 +1,7 @@
 # This file is part of cloud-init. See LICENSE file for license information.
 
 """cloud-init Integration Test Verify Script."""
-from tests.cloud_tests.instances.nocloudkvm import CI_DOMAIN
+from tests.cloud_tests import CI_DOMAIN
 from tests.cloud_tests.testcases import base