{
  "_comment": "Build with `packer build -var-file=ubuntu1604.json ubuntu.json`",
  "vm_name": "ubuntu1604",
  "cpus": "1",
  "disk_size": "65536",
  "iso_checksum": "0a03608988cfd2e50567990dc8be96fb3c501e198e2e6efcb846d89efc7b89f2",
  "iso_checksum_type": "sha256",
  "iso_url": "http://releases.ubuntu.com/16.04/ubuntu-16.04.4-server-amd64.iso",
  "memory": "512",
  "preseed" : "preseed.cfg",
  "version" : "1"
}

{
  "_comment": "Build with `packer build -var-file=ubuntu1604.json ubuntu.json`",
  "vm_name": "ubuntu1604",
  "cpus": "1",
  "disk_size": "65536",
  "iso_checksum": "c94de1cc2e10160f325eb54638a5b5aa38f181d60ee33dae9578d96d932ee5f8",
  "iso_checksum_type": "sha256",
  "iso_url": "http://releases.ubuntu.com/16.04/ubuntu-16.04.5-server-amd64.iso",
  "memory": "512",
  "preseed" : "preseed.cfg",
  "version" : "1"
}

Update URL: Ubuntu 16.04.4 -> 16.04.5
Update URL: Ubuntu 16.04.4 -> 16.04.5
