add files for packing .appx

Scripts/pack-appx.ps1

@@ -0,0 +1,26 @@
+$version = git describe --always --tags "--abbrev=0"
+
+function Update-Version($path)
+{
+    $xml = [xml](Get-Content $path)
+    $xml.Package.Identity.Version="$version"
+    $xml.Save("$path")
+}
+
+if(-not (Test-Path env:CI))
+{
+    # prapare folders
+    Remove-Item -Recurse ..\Build\Appx -ErrorAction SilentlyContinue
+    Copy-Item -Recurse ..\Build\Package ..\Build\Appx\Package
+    Copy-Item -Recurse ..\Build\Assets ..\Build\Appx\Assets
+    Copy-item ..\Build\AppxManifest.xml ..\Build\Appx
+
+    # set version to git version
+    Update-Version("..\Build\Appx\AppxManifest.xml")
+    
+    # packing
+    $packExe = 'C:\Program Files (x86)\Windows Kits\10\bin\10.0.15063.0\x86\makeappx.exe'
+    $folder = '..\Build\Appx\'
+
+    .$packExe pack /o /d ..\Build\Appx /p ..\Build\QuickLook-$version.appx
+}