Update pylint dependency to 1.9.1

Author: pitbulk

setup.py

@@ -40,7 +40,7 @@
         'test': (
             'coverage>=3.6',
             'freezegun==0.3.5',
-            'pylint==1.3.1',
+            'pylint==1.9.1',
             'pep8==1.5.7',
             'pyflakes==0.8.1',
             'coveralls==1.1',