code: public Post postReblog(String blogName, Long postId, String reblogKey) {
          return this.postReblog(blogName, postId, reblogKey, null);
      }
docs: Reblog a given post
  @param blogName the name of the blog to post to
  @param postId the id of the post
  @param reblogKey the reblog_key of the post
  @return The created reblog Post or null