Add localization framework for the GUI (en-US baseline) (#764)

Credit to @jmolinap2 for their work in #643, which was used as inspiration.

Scripts/GUI/Show-AboutDialog.ps1

@@ -32,6 +32,7 @@ function Show-AboutDialog {
     
     # Load XAML from file
     $xaml = Get-Content -Path $script:AboutWindowSchema -Raw
+    $xaml = ConvertTo-LocalizedXaml -Xaml $xaml
     $reader = [System.Xml.XmlReader]::Create([System.IO.StringReader]::new($xaml))
     try {
         $aboutWindow = [System.Windows.Markup.XamlReader]::Load($reader)