This fork add support for extracting multipart zips like .z01, .z02, ..., .zip.

The work is based on https://github.com/alexmullins/zip

The work related to Standard Zip Encryption is based on https://github.com/yeka/zip

• Call OpenReader and pass the filename of the volume with the .zip suffix to open the entire multipart archive. (Totally same to alexmullins/zip)

• Call NewMultipartReader and provide each volume as a SizeReaderAt. The volume with the .zip suffix must be the last one in the sequence.

• Defination of SizeReaderAt:

  type SizeReaderAt interface {
      Size() int64
      io.ReaderAt
  }