By Lefteris Papadimas IDOMENI, Greece (Reuters) - A tent city mushroomed around a tiny border town in northern Greece on Tuesday after thousands of migrants and refugees found their way towards western Europe barred by border shutdowns across the Balkans. People, many fleeing wars and poverty in Syria, Iraq, Afghanistan and elsewhere, continued to arrive all day at the Greek village of Idomeni on the border with Macedonia. The mood in the camp was subdued a day after Macedonian police used teargas to prevent angry migrants storming the border.