Fix docker login

deploy.ps1

@@ -9,8 +9,20 @@ $image = "stefanscherer/whoami"
 
 Write-Host Starting deploy
 if (!(Test-Path ~/.docker)) { mkdir ~/.docker }
-'{ "experimental": "enabled" }' | Out-File ~/.docker/config.json -Encoding Ascii
-docker login -u="$env:DOCKER_USER" -p="$env:DOCKER_PASS"
+# "$env:DOCKER_PASS" | docker login --username "$env:DOCKER_USER" --password-stdin
+# docker login with the old config.json style that is needed for manifest-tool
+$auth =[System.Text.Encoding]::UTF8.GetBytes("$($env:DOCKER_USER):$($env:DOCKER_PASS)")
+$auth64 = [Convert]::ToBase64String($auth)
+@"
+{
+  "auths": {
+    "https://index.docker.io/v1/": {
+      "auth": "$auth64"
+    }
+  },
+  "experimental": "enabled"
+}
+"@ | Out-File -Encoding Ascii ~/.docker/config.json
 
 $os = If ($isWindows) {"windows"} Else {"linux"}
 docker tag whoami "$($image):$os-$env:ARCH-$env:APPVEYOR_REPO_TAG_NAME"