Misplaced comment in DirectoryNode

[ebourg]

There is a misplaced comment in the DirectoryNode class, the iterator() and spliterator() methods aren't part of the POIFSViewable interface and should be under the /* ********** END begin implementation of POIFSViewable ********** */ comment.

[centic9]

Thanks for the change, I ended up reformatting the whole file some more to better fit the coding style in other areas.