The Grapes of . . . rock?
On the road with the cast at Trinity. Photo: Mark Turek.Like Boston Ballet, the venerable Trinity Rep down in Providence is celebrating its 50th anniversary this year; and to kick off the season they've gone back to their political roots, with a new production of Steinbeck's iconic The Grapes of Wrath. directed by company veteran Brian McEleney. So far, so good; Trinity's been on a roll of late, and …