Make possible the selection of the parent page only in tree view

Preconditions: Have a page with children.

Steps to reproduce:

1. Go to More Actions > Export
2. Click on Other Formats
3. Expand the tree

Expected results: The user can select only the parent or only the child page, the parent & his children, all pages, none.

Actual results: The user can select parent & his children, all, none. The user can't select only the parent page without automatically selecting all his children. As we've seen this requirement on one of our clients it would be nice to have this on the product also.
The work around is to select the parent page, which includes the children, and then deselect the child pages one by one.