* add a field to change id on currencies, only enabled for manager (because changing a currency id may reindex many related objects)
* sort and cache in CurrencyModule_getCurrencyItemList
* make symbol field not required on Currency_view




git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@9529 20353a03-c40f-0410-a6d1-a30d3c3de9de