A federal judge extended a pause Wednesday on transforming a massive Maryland warehouse into a processing facility for immigrants in a development that comes as federal immigration officials review a plan to house tens of thousands in converted industrial buildings. The Department of Homeland Security purchased the 825,000-square-foot (76,645-square-meter) building near the Washington County town of Hagerstown in January for $102.4 million. Among the 11 warehouses purchased nationwide, the