Use RepoTags & RepoDigest in inspect

To be coherent with /images/json (images command)

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

docs/reference/api/docker_remote_api.md

@@ -98,7 +98,7 @@ This section lists each version from latest to oldest.  Each listing includes a
 * `GET /volumes/(name)` get low-level information about a volume.
 * `DELETE /volumes/(name)`remove a volume with the specified name.
 * `VolumeDriver` has been moved from config to hostConfig to make the configuration portable.
-* `GET /images/(name)/json` now returns information about tags of the image.
+* `GET /images/(name)/json` now returns information about tags and digests of the image.
 * The `config` option now accepts the field `StopSignal`, which specifies the signal to use to kill a container.
 * `GET /containers/(id)/stats` will return networking information respectively for each interface.
 * The `hostConfig` option now accepts the field `DnsOptions`, which specifies a

docs/reference/api/docker_remote_api_v1.21.md

@@ -1550,7 +1550,10 @@ Return low-level information on the image `name`
           "Name" : "aufs",
           "Data" : null
        },
-       "Tags" : [
+       "RepoDigests" : [
+          "localhost:5000/test/busybox/example@sha256:cbbf2f9a99b47fc460d422812b6a5adff7dfee951d8fa2e4a98caa0382cfbdbf"
+       ],
+       "RepoTags" : [
           "example:1.0",
           "example:latest",
           "example:stable"