code: private static Chainr getChainr( ChainrInstantiator chainrInstantiator, Object chainrSpec ) {
          Chainr chainr;
          if (chainrInstantiator == null ) {
              chainr = Chainr.fromSpec( chainrSpec );
          }
          else {
              chainr = Chainr.fromSpec( chainrSpec, chainrInstantiator );
          }
          return chainr;
      }
docs: The main engine in ChainrFactory for building a Chainr Instance.
  
  @param chainrInstantiator The ChainrInstantiator to use. If null it will not be used.
  @param chainrSpec The json spec for the chainr transformation
  @return the Chainr instance created from the chainrInstantiator and inputStream