update to install 2021 version and take advantage of the Download-File function

Install-SketchUp.ps1

@@ -1,5 +1,5 @@
 ## Version of SketchUp to install
-$InstallVersion = "2020"
+$InstallVersion = "2021"
 
 ## Make sure we have an administrative token
 If ( IsAdmin )
@@ -41,12 +41,17 @@ If ( IsAdmin )
             Try { Start-Process "msiexec.exe" -ArgumentList '/X{5778f9a3-781e-16f1-a6bf-08fd59dfa77b} /qn /norestart' -Wait }
             Catch { LogErr $_.Exception.Message }
         }
-        
-        ## Set the local file name to download to
-        $FILE = '{0}{1}.exe' -f (GetTempPath),(Split-Path $URL -Leaf)
+
+        ## Uninstall SketchUp 2021
+        If ( Test-Path "${Env:ProgramFiles}\SketchUp\SketchUp 2021\SketchUp.exe" )
+        {
+            LogMsg "Uninstalling SketchUp 2021"
+            Try { Start-Process "msiexec.exe" -ArgumentList '/X{e31a06f0-fc24-f59f-5b2c-941521be9626} /qn /norestart' -Wait }
+            Catch { LogErr $_.Exception.Message }
+        }
 
         ## Download installer
-        $FILE = Download-File -URL $URL -File $FILE
+        $FILE = Download-File -URL $URL
 
         ## Install package
         Install-Program -Path $FILE -Arguments "/silent" -Delete