UI todo

[slimbuck]

This ticket lists the relatively small outstanding work items which remain after the recent UI refresh:

• [x] update color scheme to match new design
• [ ] add tooltips everywhere
• [ ] add hierarchy search
• [x] show names of loaded files
• [x] show versions of editor, engine, pcui
• [x] show github links to engine & pciu
• [ ] show bound of currently selected node
• [ ] name screenshot download based on loaded filename
• [x] remove animations correctly when loading new file
• [x] handle hierarchy node deselection
• [x] review animation controls
• [x] support camera frame of scene / currently selected node
• [x] add pause icon to playicons and use it in the animation control bar