First steps towards a decent menu

# Progress

* [x] Place menu items on top
* [x] Add decent menu background
* [x] Make sure the header is above the menu background
* [x] Add burger menu icon
* [ ] Add as much direct menu items as fit in the menu bar
* [ ] When the menu opens, fade the quick links out
* [x] Create slide open menu on the right side, interacting with the burger icon
* [x] Add decent side menu content
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