collective.js.jqueryui images are located by secondary jqueryui.css
collective.js.jqueryui images are located by secondary jqueryui.css

fixes #272

DeBortoliWines/Bika-LIMS,anneline/Bika-LIMS,veroc/Bika-LIMS,anneline/Bika-LIMS,labsanmartin/Bika-LIMS,DeBortoliWines/Bika-LIMS,rockfruit/bika.lims,rockfruit/bika.lims,labsanmartin/Bika-LIMS,veroc/Bika-LIMS,veroc/Bika-LIMS,labsanmartin/Bika-LIMS,DeBortoliWines/Bika-LIMS,anneline/Bika-LIMS