Adds a node with the given configuration in m at the given path.
In order for this method to work, the node provider must be mutable.
If you did not specify a custom node provider, the created provider is mutable.
Source
LocalNode addNode(String path, Map m) {
if (provider is! MutableNodeProvider) {
throw new Exception("Unable to Modify Node Provider: It is not mutable.");
}
return (provider as MutableNodeProvider).addNode(path, m);
}