WTOP investigative reporter Mark Segraves is the first to admit that being a radio man has sometimes made him a little too relaxed about his appearance. After being famously called out by former D.C. Mayor Anthony Williams for showing up to press conferences in flip-flops and Hawaiian shirts, Segraves says he’s made an effort over the last couple years to dress more professionally when he’s on the job. Still, DCist occasionally spots him staking…