public static <S,E>void insertBeforeStep(final Step<S,E> insertStep,final Step<E,?> afterStep,final Traversal.Admin<?,?> traversal){
  traversal.addStep(stepIndex(afterStep,traversal),insertStep);
}

public static < S , E > void insertBeforeStep ( final Step < S , E > insertStep , final Step < E , ? > afterStep , final Traversal . Admin < ? , ? > traversal ) { traversal . addStep ( stepIndex ( afterStep , traversal ) , insertStep ) ; }
insert a step before a specified step instance .
