MILAN — With hemlines soaring, designers aren’t missing one opportunity to do legwear — and to do it in ways that match the latest rtw trends stride for stride. Some of the choicest examples: the heathery sweater knits at Dolce & Gabbana; Krizia’s two-toned hose meant to mimic school-girlish over-the-knee socks and the silvery opaques Versace sent out at Istante.