Luke

Add include guard to materials

1

Prevents material already defined errors when adding multiple types of camera to a robot. I was making a URDF for the d455 based on the d435 as I have a...

Allow multiple parents for same node in mindmap or make child node by reference to node id of other node

1

### Proposal Sometimes a child node in a mind map may logically belong to multiple parent nodes. Nodes can already be assigned `id`s so it would be desirable to add...