get packer on appveyor

appveyor.yml

@@ -13,6 +13,7 @@ install:
   - SET "PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
   - python --version
   - pip install -r %requirementsFile%
+  - tools\get-packer.ps1
 
 build: off
 

tools/get-packer.ps1

@@ -0,0 +1,11 @@
+$latestVersion = [string](((Invoke-RestMethod -Uri https://releases.hashicorp.com/packer/) -split "\n" | select-string -pattern "(\d+\.){2,3}\d+" | foreach {$_.matches} | select -expandproperty value) | %{[System.Version]$_} | sort | select -last 1)
+$url = "https://releases.hashicorp.com/packer/$latestVersion/packer_$latestVersion_windows_amd64.zip"
+$output = "$PSScriptRoot\packer.zip"
+
+(New-Object System.Net.WebClient).DownloadFile($url, $output)
+$extractPath = (get-item $PSScriptRoot).parent.FullName
+$shell = new-object -com shell.application
+$zip = $shell.NameSpace($output)
+foreach($item in $zip.items()) {
+	$shell.Namespace("$extractPath").copyhere($item)
+}