code: public boolean unpackBoolean()
              throws IOException
      {
          byte b = readByte();
          if (b == Code.FALSE) {
              return false;
          }
          else if (b == Code.TRUE) {
              return true;
          }
          throw unexpected("boolean", b);
      }
docs: Reads true or false.
  
  @return the read value
  @throws MessageTypeException when value is not MessagePack Boolean type
  @throws IOException when underlying input throws IOException