Replace build scripts with prepare scripts

Packer/scripts/vm-guest-tools.ps1

@@ -15,6 +15,8 @@ if ("$env:PACKER_BUILDER_TYPE" -eq "vmware-iso") {
 
     if (!(Test-Path "C:\Windows\Temp\windows.iso")) {
         Try {
+            # Disabling the progress bar speeds up IWR https://github.com/PowerShell/PowerShell/issues/2138
+            $ProgressPreference = 'SilentlyContinue'
             $pageContentLinks = (Invoke-WebRequest('https://softwareupdate.vmware.com/cds/vmw-desktop/ws') -UseBasicParsing).Links | where-object {$_.href -Match "[0-9]"} | Select-Object href | % { $_.href.Trim('/') }
             $versionObject = $pageContentLinks | %{ new-object System.Version ($_) } | sort-object -Descending | select-object -First 1 -Property:Major,Minor,Build
             $newestVersion = $versionObject.Major.ToString()+"."+$versionObject.Minor.ToString()+"."+$versionObject.Build.ToString() | out-string