By Emily Schneider There’s a scene in Sister Act 2 where Whoopi Goldberg confronts a young teenage girl about joining her school’s choir. She describes the book “Letters to a Young Poet” as follows: “A fellow used to write to him and say: ‘I want to be a writer. Please read my stuff.’ And Rilke says to this guy: ‘Don’t ask me about being a writer. lf when you wake up in the morning you can think of nothing but writing…then you’re a writer.’ ” Writing requires energy. It requires strength of mind. It requires emotional fortitude. Most of all, it requires your heart. If your heart’s not in it,…