Reimplement the Hammer pane embedded asset browser as a dock widget, tabify it at the bottom alongside our new C# one, always show the legacy first (for now). And in general tidy up / simplify the implementation of this
Add these asset browser dock widgets to the View->Toolbars menu
Need to setObjectName on these so they saveState properly
Remove QHeaderView from asset browser grid layout, not useful takes up a shit load of space
Legacy asset browser icon sizes match our new asset browser icon sizes, makes the medium icons actually usable in embedded browsers