By Denny Dyroff, Staff Writer, The Times  Davy Knowles On January 19, two acts from the British Isles will be performing at venues in the area. But, neither act hails from a country that is part of Great Britain or the United Kingdom. Davy Knowles, who will perform at the Sellersville Theater (24 West Temple Avenue, Sellersville, 215-257-5808, www.st94.com), is a native of the Isle of Man. We...