CORVALLIS — A visit from defending Pac-12 Conference champion Stanford, a Friday night home date with USC and a Reser Stadium showdown with rival Washington highlight a six-game home schedule for the 2013 football season for Oregon State. The Beavers, coming off a 9-4 campaign and a No. 19 national ranking, open the ’13 slate on Aug. 31 against Football Championship Subdivision power Eastern Washington at home. The University of Hawaii visits Corvallis the following Saturday on Sept. 7 as OSU opens the year with back-to-back home games for the first time since 2005 after the 2012 schedule was modified …