WOODSTOCK – Mary Zimmerman has a talent for putting performances onstage that weren’t meant to be there. She specializes in adapting classic texts, such as “The Odyssey” and “Wonderful Town,” and directing them for onstage performances in a vision that’s entirely her own. For more than 25 years, Zimmerman has made a career of seeing something for what it’s not and bringing it to life onstage for what it could be.