code: function onlineExist(pattern, opts, callback) {
    var args = verify(pattern, opts, callback);
    opts = args.opts;
    callback = args.callback;
  
    var refs = 'refs/heads/' + cache.branch;
    request(refs, opts, function cb(err, res) {
      if (res === false) {
        refs = 'refs/tags/' + cache.branch;
        request(refs, opts, callback);
        return;
      }
      callback(null, true);
    });
  }
docs: Check using `user/repo#branch` if tag or branch exists.
  
  @name onlineExist
  @param  {String}   `pattern`
  @param  {Object}   `opts`
  @param  {Function} `callback`
  @api public