CategoryTool: Remove unused "types" import.

Also, reorder imports to follow python style: standard modules before
others.

product/CMFCategory/CategoryTool.py

@@ -31,6 +31,7 @@
 ERP portal_categories tool.
 """
 from collections import deque
+import re
 from BTrees.OOBTree import OOTreeSet
 from OFS.Folder import Folder
 from Products.CMFCore.utils import UniqueObject
@@ -47,10 +48,6 @@ from Products.CMFCore.PortalFolder import ContentFilter
 from Products.CMFCategory.Renderer import Renderer
 from Products.CMFCategory.Category import Category, BaseCategory
 from OFS.Traversable import NotFound
-import types
-
-import re
-
 from zLOG import LOG, PROBLEM, WARNING, ERROR
 
 _marker = object()