As Myanmar celebrates its 99th National Day today, the challenge of how best to balance its rich architectural and cultural heritage with the demands of modern development is as important as ever.Nowhere is this more apparent than in the port city of Yangon, the country’s former capital which has the distinction of having the densest concentration of colonial-era buildings of any city in Asia.The biggest city in Myanmar, Yangon’s 19th- and early 20th-century colonial architecture was slowly r