code: public GlResourceBuilder plus() throws GlClientException {
          alleles.clear();
          alleleLists.clear();
          haplotypes.add(haplotype);
          genotype = client.createGenotype(haplotypes);
          return this;
      }
docs: Return this gl resource builder configured with an plus operator ('<code>+</code>' character).  The
  plus operator combines two ore more haplotypes into a genotype.
  
  @return this gl resource builder configured with an plus operator ('<code>+</code>' character)
  @throws GlClientException if an error occurs