function wrapCallback(callback)
{
  var stream = this;

  var wrapped = function(error, result)
  {
    return finisher.call(stream, error, result, callback);
  };

  return wrapped;
}
Wraps provided callback function
allowing to execute snitch function before
real callback

@this    ReadableAsyncKit#
@param   {function} callback - function to wrap
@returns {function} - wrapped function