Attempt to fix public enum values not being exported.

Cython/Compiler/ParseTreeTransforms.py

@@ -677,7 +677,10 @@ property NAME:
         return None
     
     def visit_CEnumDefNode(self, node):
-        return None
+        if node.visibility == 'public':
+            return node
+        else:
+            return None
 
     def visit_CStructOrUnionDefNode(self, node):
         return None

tests/run/public_enum.pyx

+__doc__ = u"""
+>>> BAR
+3
+"""
+
+cdef public enum FOO:
+    BAR = 3