Introducing experimental admin sidebar navigation

[martin (Martin Brennan)]

@tobiaseigen

Yeah, I miss this too! You have to know to go to /admin/upgrade to upgrade, or use the link on the admin landing page if you need to upgrade.

The next step here is to make the two menus really identical - so they function exactly the same way. Right now they are not. Martin has this on his list. Then we’ll look at optimizing further.

I’ve been working on a PR for this today, I’ve just got to fix some review comments then I can merge. Here is a preview (side note, we are also changing the Upgrade wording to Update some point soon):