The Travis Heights neighborhood of South Austin, one of the city's more notable concentrations of historic domestic architecture, could attain its long-sought admission to the National Register of Historic Places by next year. The Texas Historical Commission's State Board of Review unanimously approved the 353-acre district's nomination to the federal register at a meeting last month, so the only step left is the verification of the State Historic Preservation Officer (SHPO) before the nomination is sent off to the National Park Service -- a process the state says should take only a . . .