Separate drawer header, default, and footer elements

[oliveryasuna]

Describe the current way to archive your requirement

I wrap LeftNavigationItems in a VerticalLayout applying CSS to make it match.

Describe the solution you'd like

It seems that the separation of drawer header, default, and footer is purely for code organization, as there is no reflection of these sections in the generated HTML. For example, I want to stick the footer section on the bottom of the drawer.

I believe the HTML should separate these three sections.