A node can inherit the permission of its father
In the "edit node" (edit menu) page, a checkbox is added next to "user role permission". When it's checked, the node dynamicaly inherits all the permissions from its parent. That means a change to the parent's permission list affects all its children nodes which have the checkbox on.
Technically, a permission (table pds_core_
implement inheritance in the NAVIGATION_
add the checkbox to the menu edit page: DONE