When right-clicking a notebook to create a new section, offer the distinction between "New section" and "New sub-section"

[nekohayo]

Right-clicking at random into the Sections and choosing "New section" created a section inside a section, which I did not expect. Non-technical users will not necessarily think of right-clicking the "Sections" row rather than "whatever area in the sections area" to create a new top-level section, so I think it would be worth offering the two actions in the right-click menu when right-clicking a section.