Image courtesy WMATA As expected, the WMATA board today appointed former New Jersey transit chief Richard Sarles as its new interim general manager. Sarles, who told reporters today that he is not interested in the GM gig long-term, will earn $25,000 a month while the board conducts a search for a permanent replacement for John Catoe. Catoe is set to retire on April 2, but Sarles will formally start on March 29, giving the…