code: public BTreeKeySerializer<?> bTreeKeySerializerFor( TypeFactory<?> type,
                                                          boolean pack ) {
          return serializers.bTreeKeySerializerFor(type.getType(), type.getComparator(), pack);
      }
docs: Obtain a serializer for the given key type.
  
  @param type the type; may not be null
  @param pack true if the serializer can/should pack keys together when possible, or false otherwise
  @return the serializer