* scaffold new component + remove storing of expanded state
* some padding fixes
* simplify!
* move browse back to being a child of dashboards
* behaviour working
* improve child matcher to look recursively
* increase NavBarMenu zIndex to ensure it overlays explore drawer
* some renaming
* fix unit test
* make dashboards a top level item again and make chevrons their own buttons
* remove active background state
* Finished tweaks
* remove theme change
* Remove exit animation
* align button centrally + fix empty message alignment
* only show the empty message if there are no children
* ensure overflowing menu items truncate correctly
Co-authored-by: Ashley Harrison <ashley.harrison@grafana.com>
