Fix Py3 regression

CHANGES.rst

 Change History
 **************
 
+2.2.3 (2014-10-30)
+==================
+
+- Fix #197, Python 3 regression
+  [aclark4life]
+
 2.2.2 (2014-10-30)
 ==================
 

setup.py

@@ -12,7 +12,7 @@
 #
 ##############################################################################
 name = "zc.buildout"
-version = "2.2.2"
+version = "2.2.3"
 
 import os
 from setuptools import setup

src/zc/buildout/easy_install.py

@@ -653,7 +653,7 @@ class Installer:
                 if dist is None:
                     try:
                         dist = best[req.key] = env.best_match(req, ws)
-                    except pkg_resources.VersionConflict, err:
+                    except pkg_resources.VersionConflict as err:
                         raise VersionConflict(err, ws)
                     if dist is None:
                         if dest: