By Martyn Herman RIO DE JANEIRO, Aug 10 (Reuters) - Veteran American Kristin Armstrong completed a remarkable return to cycling by winning a third consecutive gold medal in the time trial on a rainy morning at the Rio Games on Wednesday. A day before her 43rd birthday Armstrong, the last to tackle the 29.7km course, sped over the finish line 5.55 seconds faster than Russian Olga Zabelinskaya. Road race champion Anna van der Breggen of the Netherlands was in third place. More...