-Added constructor nodes, specialized and conversion ones.
-Cleaned up how unconnected input default values are shown and edited (much cleaner)
-Dragging scene nodes into graph makes a call dialog appear by deault
-Dragging properties into graph is set by default, not get
-fixed dragging internal functions into graph
-Block switches to 2d/3d editor if editing visual script
-Added cast node in flow control
-Added ability to do RPC in visual script
-Comment nodes
-Fix bug with inverted cable in connecting backwards
-Copy and paste nodes, including from different scripts
With this, visual script is almost done (missing registering custom nodes from addon).
All this is probably pretty broken, too and needs a lot of testing.
