base_category using prefered base category for this portal_type
- remove my_variation_base_category_list field from ApparelCloth_view because
now base_category is automatically selected by system preferences

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@29370 20353a03-c40f-0410-a6d1-a30d3c3de9de