Modified .gitmodules and add username
Modified .gitmodules and add username

columbia/xtern,columbia/xtern,hemingcui/xtern_with_paxos,columbia/xtern,hemingcui/xtern_with_paxos,columbia/xtern,hemingcui/xtern_with_paxos,hemingcui/xtern_with_paxos,hemingcui/xtern_with_paxos,columbia/xtern,columbia/xtern