Support for reading Docker multi-arch images about terraform-provider-docker

[vprakash-seatgeek]

I have implemented this in #565. If you read the alpine:latest image as in the Potential Terraform Configuration section above, the resulting data object looks like this:

{
  "id" = "library/alpine:latest"
  "insecure_skip_verify" = false
  "manifests" = toset([
    {
      "architecture" = "386"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:f953af9881ecc0c32d60d9c0438ea2cff465900c4c0fa5601bcc3c996e103cd7"
    },
    {
      "architecture" = "amd64"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:c0669ef34cdc14332c0f1ab0c2c01acb91d96014b172f1a76f3a39e63d1f0bda"
    },
    {
      "architecture" = "arm"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:200d1839f0645e5005181b6e6ebd46a040826dec2d6af9320b0f597ec9d27242"
    },
    {
      "architecture" = "arm"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:2627e55acb9ac183f1c94e6a44f869620d164bbb10d7c42b29df08513eb20c29"
    },
    {
      "architecture" = "arm64"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:30e6d35703c578ee703230b9dc87ada2ba958c1928615ac8a674fcbbcbb0f281"
    },
    {
      "architecture" = "ppc64le"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:0d3a7ea444301e2f42df027055f2e272b437bd23a4f117336e0f966ad3ed9bba"
    },
    {
      "architecture" = "s390x"
      "media_type" = "application/vnd.docker.distribution.manifest.v2+json"
      "os" = "linux"
      "sha256_digest" = "sha256:feb7b809e29452823ebb369b4a8333686a179a93746744d6740fae1c0e530e87"
    },
  ])
  "name" = "alpine:latest"
}