Safer to pylint on Python 3

setup.py

@@ -1,7 +1,6 @@
 import codecs
 import os
 import re
-import sys
 
 from setuptools import setup
 from setuptools import find_packages
@@ -52,14 +51,13 @@ install_requires = [
 ]
 
 dev_extras = [
-    # Pin astroid==1.3.5, pylint==1.4.2 as a workaround for #289
-    'astroid==1.3.5',
+    'astroid',
     'coverage',
     'ipdb',
     'pytest',
     'pytest-cov',
     'pytest-xdist',
-    'pylint==1.4.2',  # upstream #248
+    'pylint>=1.8.4',
     'tox',
     'twine',
     'wheel',