Coldplay, Noel Gallagher's High Flying Birds and Florence And The Machine have been revealed as the biggest selling rock acts of 2011.According to The Official Charts Company, Coldplay scored both the biggest selling rock single of 2011 with 'Paradise', which sold over 410,000 copies and the biggest selling album with their fifth effort 'Mylo Xyloto', which sold over 900,000 copies despite only being released in October.Noel Gallagher's debut solo effort was the second biggest seller in the album stakes with sales just shy of 500,000. He was followed by Florence And The Machine, who were narro