More layer manipulation!

This was, I think, the most enjoyable coding session in stardance because coding went smoothly with almost no headaches figuring out why things do not work. It also brought many new features after many devlogs of mostly debugging.

features

• visibility button to show/hide paths
• Dragging and resizing layers so the path only renderes at the given boundaries
• Dragging layers outside of the visible scroller area expands the scroller size (no current way of retracting it. Open for suggestions :D)
• Different mouse cursors for different layer manipulations

I’m thinking now of two missing features of the timeline: dragging keyframes, and reordering layers, then I might consider the timeline milestone finished (maybe will need some cleaning up) and I could start on the next milestone: graph editors