Revert "Make sure CMFCategory product is imported before ERP5Type.Core.Folder"

This reverts commit 0af3e8f6.

This is not required anymore since ERP5Type.PropertySheet is a dynamic module
(commit 9ddcbfc1).

product/ERP5Type/Core/__init__.py

-# Make sure CMFCategory product is imported before ERP5Type.Core.Folder
-# because Folder needs PropertySheet.CategoryCore
-# This is important for ZEO server which may need to import conflict-resolution
-# classes from products that depend (at 'import' time) directly on Folder.
-import Products.CMFCategory