Add the possibility to rename part of the children pages of the renamed page

Currently when renaming/moving a page using the standard "Rename/Move" feature it is possible to preserve all children pages of the renamed page by moving them to the new location. See screenshot :

It can be really useful if we could have the possibility to move only part of the children pages as we do for the export feature for example. We could have a document tree of children pages with checkboxes to select the wanted children pages.