WILLIAMSBURG, Virginia (Reuters) - House Republicans signaled on Thursday they might support a short-term extension of U.S. borrowing authority next month so they can move on to budget battles that could offer them more political leverage. The move, described as under consideration by House of Representatives Budget Committee Chairman Paul Ryan, appears to be aimed at getting President Barack Obama and his Democrats to start negotiating with them on spending cuts without Republicans being blamed for a debt default and any resulting chaos in financial markets. ...