- use ApparelColourRange instead of VariationRange (revert of r29344) because ApparelColourRange defined a default value (color) usefull for this class.
- also partially revert r29343 in the same way
- use _list for variation_base_category and optional_variation_base_category fields

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@29434 20353a03-c40f-0410-a6d1-a30d3c3de9de