[ChainNode] avoid cyclic handling

[vatson]

There are a couple of cases with cyclic handling.

Problem Node adds itself as the next node.
Solution The issue can be solved by adding a check in AbstractChainNode::nextNode() method.

Problem Imagine a scheme: n1 -> n2 -> n1. In other words, these nodes link to each other.
Solution I dunno. I will be glad to hear your opinion.

[makasim]

I dont think we should take care about it. A developer should test his chain in dev and he will catch the nesting error.