private static ChainsModel createChainsModel(ChainsConfig chainsConfig) {
        ChainsModel model = new ChainsModel();
        for (ChainsConfig.Chains chainConfig : chainsConfig.chains()) {
            model.register(
                    createChainSpecification(chainConfig));
        }
        return model;
    }
Builds a chains model from config.

@author Tony Vaagenes
container-core/src/main/java/com/yahoo/component/chain/model/ChainsModelBuilder.java