"STAIN," a short play by Medford playwright Laura Olifiers, is being presented online as part of the Playwrights’ Platform 48th Festival of New Plays. In "STAIN," on the eve of Allison’s wedding her two sisters, Liz and Sarah, discover a stain on her wedding dress.  Their responses to it reveal deeper truths about their family dynamic and personal relationships. Directed by Kelly Smith, the play features actors Adriana Alvarez as Allison, Alissa Cordeiro as Liz, Meredith Saran as Sarah, and…