Alexandria, VA — Kem is standing before an audience, but this time he’s not on stage. The artist is dressed casually, wearing a sweatsuit, baseball cap and sneakers. Though he’s not singing at the time, he is doing a bit of preaching:“I’m a living witness,” he tells the group. “Don’t quit-–don’t give up before your miracle happens”. Kem is speaking to residents of the Carpenter’s Shelter, in Alexandria, Virginia, a homeless shelter just a few miles outside of Washington, DC, where he just finis…