fix win_get_url var renames ala xpicio fix PR #2378

reimplements #2378 sans formatting merge conflicts

lib/ansible/modules/windows/win_get_url.ps1

@@ -55,22 +55,22 @@ if($skip_certificate_validation){
 $force = Get-Attr -obj $params -name "force" "yes" | ConvertTo-Bool
 
 If ($force -or -not (Test-Path $dest)) {
-    $client = New-Object System.Net.WebClient
+    $webClient = New-Object System.Net.WebClient
     if($proxy_url) {
         $proxy_server = New-Object System.Net.WebProxy($proxy_url, $true)
         if($proxy_username -and $proxy_password){
             $proxy_credential = New-Object System.Net.NetworkCredential($proxy_username, $proxy_password)
             $proxy_server.Credentials = $proxy_credential
         }
-        $client.Proxy = $proxy_server
+        $webClient.Proxy = $proxy_server
     }
 
     if($username -and $password){
-        $client.Credentials = New-Object System.Net.NetworkCredential($username, $password)
+        $webClient.Credentials = New-Object System.Net.NetworkCredential($username, $password)
     }
 
     Try {
-        $client.DownloadFile($url, $dest)
+        $webClient.DownloadFile($url, $dest)
         $result.changed = $true
     }
     Catch {
@@ -89,7 +89,7 @@ Else {
         $webRequest.Method = "GET"
         [System.Net.HttpWebResponse]$webResponse = $webRequest.GetResponse()
         
-        $stream = New-Object System.IO.StreamReader($response.GetResponseStream())
+        $stream = New-Object System.IO.StreamReader($webResponse.GetResponseStream())
         
         $stream.ReadToEnd() | Set-Content -Path $dest -Force -ErrorAction Stop