By Steve Keating BIRMINGHAM, England (Reuters) -Swimmer Emma McKeon became the most successful Commonwealth Games athlete of all-time on Sunday, leading an Australian sweep of the women’s 50 metre freestyle to claim a record 11th gold medal. It was a night of milestones at the Sandwell Aquatic Centre as moments earlier South African Chad Le Clos had joined shooters Michael Gault and Phil Adams as the most decorated Games athletes ever when he snatched his 18th medal by picking up a silver in the men’s 200 metres butterfly. Australia then ended the evening with a bang, powering to gold in the w…