Node getNext() {
			if (isExplored()) {
				return null;
			}

			Node node = new Node(this, unexplored.pop());
			return node;
		}
Simple class to maintain a relationship between a given node and its children that need
processing.  It also knows if it has been found in a path from start to end.
Ghidra/Framework/Graph/src/main/java/ghidra/graph/algo/IterativeFindPathsAlgorithm.java