code: function remove(id, callback) {
          repo.contents(id).fetch({
              ref: options.branch
          }, function(err, info) {
              if (err) return callback(err);
              repo.contents(id).remove({
                  branch: options.branch,
                  sha: info.sha,
                  message: '-'
              }, function(err, res) {
                 callback(err, res, id);
              });
          });
      }
docs: Remove an item from the database given its id  and a callback.
  
  @param {String} id
  @param {Function} callback called with (err, result, id)