MONDAY >> If you’re not high-tailing it to the Maryland end of the Orange line to see the Redskins take on the Vikings, you may want to pay the Black Cat’s backstage a visit to see The Whigs. This trio from Athens, GA has been called the “best unsigned band in America” by Rolling Stone. $8, 9 p.m. >> The haunting, violin-driven alt country of the Black Swans is coming our way. Catch these boys…