Namespace is added on each parent element for dc:creator

[MrPropre]

Hi, @suin

I notice that when I use <dc:creator> element, the namespace attribute is added on the current element, and on each parent element of it.
For example, when I want to add the creator of an item, the xmlns:dc namespace attribute is added on the <dc:creator> element, but also on <item>, <channel> and <rss> elements.
I think namespace attributes should only be added on the <rss> attribute, so this could be an issue.

I hope this library is still maintained.

Thank you in advance ! 😄

[MrPropre]

@suin Is this library maintained anymore?