Minor refactoring (DRY) - delegated two methods with varargs to their Iterable variants

I've just started using jOOX and I think it's really great job (makes DOM traversal much less verbose and nicer for eyes). While browsing your code I saw some (unnecessarily) duplicated lines, made a quick commit and filled this pull request. Hope it'll be helpful!

BTW: Should I ask for new features here on Github or on Google Code?