domain: add arguments for the function in domain.run()

PR for https://github.com/joyent/node/issues/7193
I think we should have a standard function to handle the arguments in the most optimal way, something like this:

```js
util.getArgumentsAsArray = function (args, slice) {
  var length = args.length - slice;
  var arr = new Array(length);
  var index = slice;

  while (index < length) {
    arr[index - slice] = args[index];
    index++;
  }

  return arr;
};
```

This function may be used in `setTimeout()`, `setInterval()`, `setImmediate()`, `EventEmitter.emit()`, `domain.run()`, in some future implementation with custom arguments and in third-party modules.