code: public DERObject toASN1Object()
      {
          ASN1EncodableVector   v = new ASN1EncodableVector();
  
          if (permitted != null)
          {
              v.add(new DERTaggedObject(false, 0, permitted));
          }
  
          if (excluded != null)
          {
              v.add(new DERTaggedObject(false, 1, excluded));
          }
  
          return new DERSequence(v);
      }
docs: /*
  NameConstraints ::= SEQUENCE {
  permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
  excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }