SARASOTA, Fla. — Long before Florida became a land of sprawling resorts, luxury condominiums and billion-dollar developments, one of America’s richest and most famous showmen looked across Sarasota Bay and imagined something extraordinary. His name was John Ringling. Today, his 66-acre estate remains one of Florida’s most remarkable landmarks—a place where a Venetian-style mansion, priceless European artwork and the strange and spectacular history of the American circus exist