File _constraints of Package kubernetes1.6

<constraints>
  <hardware>
    <memory>
      <size unit="G">4</size>
    </memory>
    <physicalmemory>
      <size unit="G">4</size>
    </physicalmemory>
    <disk>
      <size unit="G">6</size>
    </disk>
  </hardware>
</constraints>