Description: Fix test failure caused by changes in Python 3.3
Author: Benjamin Drung <benjamin.drung@profitbricks.com>

--- a/versiontools/tests.py
+++ b/versiontools/tests.py
@@ -134,8 +134,12 @@
         except Exception:
             e = sys.exc_info()[1]
             self.assertTrue(isinstance(e, DistutilsSetupError))
-            self.assertEqual(str(e), "Unable to import 'nonexisting': "
-                                      "No module named nonexisting")
+            if sys.version_info[:2] >= (3, 3):
+                error_msg = "No module named 'nonexisting'"
+            else:
+                error_msg = "No module named nonexisting"
+            self.assertEqual(str(e), "Unable to import 'nonexisting': " +
+                                      error_msg)
 
     def test_not_found(self):
         version = ':versiontools:versiontools:__nonexisting__'