This issue is related to the ongoing discussion in #1439

I noticed that the logic of the methods resetTree
and haltAllActions is problematic.

A halted node must set the status to IDLE and an idled node must always call halt() first to do a correct cleanup of RUNNING asynchronous nodes.

A work around, for the time being, would be to have a single method like this:

    static void haltTree(BT::TreeNode * root_node)
    {
        // the halt should propagate to all the node if the nodes
        // have been implemented correctly
        root_node->halt();
        root_node->setStatus(NodeStatus::IDLE);

        //but, just in case.... 
        auto visitor = [](BT::TreeNode * node) {
            node->halt();
            node->setStatus(BT::NodeStatus::IDLE);
        };
        BT::applyRecursiveVisitor(root_node, visitor);
    }

In practice, this same problem might affect many users, therefore I made a breaking change in my API:
BehaviorTree/BehaviorTree.CPP@4f30e3a

I know people will hate me, but it is the only way to forbid users from repeating this same error.

What do you think?