Update Windows Server install instructions (#5129)

_config.yml

@@ -113,7 +113,7 @@ defaults:
       path: "engine"
     values:
       assignee: "mstanleyjones"
-      win_server_zip_url: "https://download.docker.com/components/engine/windows-server/17.06/docker-17.06.2-ee-4.zip"
+      win_latest_build: "docker-17.06.2-ee-4"
   - scope:
       path: "kitematic"
     values:

engine/installation/windows/docker-ee.md

@@ -6,6 +6,10 @@ redirect_from:
 - /docker-ee-for-windows/install/
 ---
 
+{% capture filename %}{{ page.win_latest_build }}.zip{% endcapture %}
+{% capture download_url %}https://download.docker.com/components/engine/windows-server/{{ site.docker_ee_version }}/{{ filename }}{% endcapture %}
+
+
 Docker Enterprise Edition for Windows Server 2016 (*Docker EE*) enables native
 Docker containers on Windows Server 2016. The Docker EE installation package
 includes everything you need to run Docker on Windows Server 2016.
@@ -82,8 +86,7 @@ installs, or install on air-gapped systems.
 
     ```ps
     # On an online machine, download the zip file.
-    PS> invoke-webrequest -UseBasicparsing -Outfile docker.zip
-    {{ page.win_server_zip_url }}
+    PS> invoke-webrequest -UseBasicparsing -Outfile {{ filename }} {{ download_url }}
     ```
 
 2.  Copy the zip file to the machine where you want to install Docker. In a
@@ -92,10 +95,10 @@ installs, or install on air-gapped systems.
 
     ```ps
     # Extract the archive.
-    PS> Expand-Archive docker.zip -DestinationPath $Env:ProgramFiles
+    PS> Expand-Archive {{ filename }} -DestinationPath $Env:ProgramFiles
 
     # Clean up the zip file.
-    PS> Remove-Item -Force docker.zip
+    PS> Remove-Item -Force {{ filename }}
 
     # Install Docker. This will require rebooting.
     $null = Install-WindowsFeature containers