A downtown Seattle building that used to house the branch of the Federal Reserve Bank was placed this week on the National Register of Historic Places. Developers have eyed the prime property at 1015 Second Ave. for years. The listing does not mean that the half-block property, which is zoned to allow construction of a high-rise, cannot be redeveloped. But doing so now will be more complicated. In 2008, after branch operations were moved to Renton, Sabey Corp., of Tukwila, entered into a deal…