code: public <V> V addVertex(Class<V> clazz) {
          IFramer<Element, V> framer = registry.get(clazz);
          Vertex v = graph.addVertex(framer.label());
          return framer.frameNew(v, this);
      }
docs: Add a linked vertex of type {@link V} to the graph. The value will be the lowercase value of the class.
  
  @param <V>   Framing class annotated with  {@link peapod.annotations.Vertex}
  @param clazz a framing class annotated with {@link peapod.annotations.Vertex}
  @return The newly created labeled linked vertex