setup.py: drop Python 3 check

Author: mruffalo

setup.py

@@ -6,11 +6,6 @@
 
 here = path.abspath(path.dirname(__file__))
 
-# Make sure isn't using Python 3, since we currently don't support that
-import sys
-if not sys.version_info[0] == 2:
-    sys.exit("Apologies! Python 3 isn't supported yet.")
-
 setup(
     name='cmapPy',