began new infrastructure

Yep, this is another one of my "famous" sweeping rewrites. Expect things to break.

Goals for this are:
- Greatly simplify node connections (particularly with arrays) so the code requires less maintenance/is more stable
- Redesign node structure to address issues where UI would stall for lengthy periods of time
- Less reliance on shared ptrs/greater reliance on QObject system for inheritance/memory management
- General code cleanup and improvements

app/widget/keyframeview/keyframeview.cpp

@@ -42,7 +42,7 @@ void KeyframeView::SceneRectUpdateEvent(QRectF &rect)
   rect.setHeight(max_scroll_);
 }
 
-void KeyframeView::AddKeyframe(NodeKeyframePtr key, int y)
+void KeyframeView::AddKeyframe(NodeKeyframe* key, int y)
 {
   QPoint global_pt(0, y);
   QPoint local_pt = mapFromGlobal(global_pt);