Link node/link in node/link out node

[TotallyInformation]

Best to keep this to 1 thread I think. Closing this one for now - let me know if it needs reopening.

Custom nodes to inherit linking from link-in, link-out nodes

I'd like to be able to add virtual wires between my own custom nodes and have them behave similar to how link-in / link-out pair does it - shows the normally invisible port with a dashed wire when selected, possibly with many wires leading to other tabs, maintain the linkage even on cut/copy/paste/undo, handle message passing between ... the only customization would be the UI editor so that my custom node can decide the list of selectable source/target nodes based on custom criteria (such as the…