giD v0.9.2 GObject Introspection binding repository and generator with Gtk4 support

[Element Green]

Here is the Clipboard example from the giD Gtk4 Examples project 
to get an idea of what programming with giD and Gtk4 looks like:

```D
module clipboard;

import Gdk.Clipboard;
import Gdk.ContentProvider;
import Gdk.Display;
import Gdk.Texture;
import Gio.AsyncResult;
import GObject.ObjectG;
import GObject.Value;
import Gtk.Application;
import Gtk.ApplicationWindow;
import Gtk.Box;
import Gtk.Button;
import Gtk.Entry;
import Gtk.Picture;
import Gtk.Types : Align, Orientation;
import Pango.Types : Weight, Style, Underline;

import example;

class ClipboardExample : Example
{
     override @property ExampleCategory category() { return 
ExampleCategory.Default; }
     override ApplicationWindow createWindow(Application app) { 
return new ClipboardWindow(app); }
}

class ClipboardWindow : ApplicationWindow
{
     Clipboard clipboard;
     Entry entry;
     Picture picture;

     this(Application app)
     {
         super(app);
         setTitle("Clipboard Example");

         auto box = new Box(Orientation.Vertical, 12);
         setChild(box);

         clipboard = Display.getDefault.getClipboard;

         auto textBox = new Box(Orientation.Horizontal, 6);
         textBox.setHomogeneous(true);
         box.append(textBox);

         entry = new Entry;
         entry.setText("Some text you can copy");
         auto buttonCopyText = Button.newWithLabel("Copy Text");
         buttonCopyText.connectClicked(&onCopyTextClicked);
         auto buttonPasteText = Button.newWithLabel("Paste Text");
         buttonPasteText.connectClicked(&onPasteTextClicked);

         textBox.append(entry);
         textBox.append(buttonCopyText);
         textBox.append(buttonPasteText);

         auto imageBox = new Box(Orientation.Horizontal, 6);
         box.append(imageBox);

         picture = Picture.newForFilename("images/dlang_logo.png");
         picture.setHexpand(true);
         auto buttonCopyImage = Button.newWithLabel("Copy Image");
         buttonCopyImage.setValign(Align.Center);
         buttonCopyImage.connectClicked(&onCopyImageClicked);
         auto buttonPasteImage = Button.newWithLabel("Paste 
Image");
         buttonPasteImage.setValign(Align.Center);
         buttonPasteImage.connectClicked(&onPasteImageClicked);

         imageBox.append(picture);
         imageBox.append(buttonCopyImage);
         imageBox.append(buttonPasteImage);
     }

     void onCopyTextClicked(Button button)
     {
         clipboard.set(new Value(entry.getText));
     }

     void onPasteTextClicked(Button button)
     {
         clipboard.readTextAsync(null, &clipboardReadTextAsync);
     }

     void clipboardReadTextAsync(ObjectG obj, AsyncResult result)
     {
         if (auto text = clipboard.readTextFinish(result))
             entry.setText(text);
     }

     void onCopyImageClicked(Button button)
     {
         if (auto texture = cast(Texture)picture.getPaintable)
         {
             auto content = 
ContentProvider.newForBytes("image/png", texture.saveToPngBytes);
             clipboard.setContent(content);
         }
     }

     void onPasteImageClicked(Button button)
     {
         clipboard.readTextureAsync(null, 
&clipboardReadTextureAsync);
     }

     void clipboardReadTextureAsync(ObjectG obj, AsyncResult 
result)
     {
         if (auto texture = clipboard.readTextureFinish(result))
             picture.setPaintable(texture);
     }
}
```