added GTK4 support

examples/gaction.nim

@@ -1,27 +0,0 @@
-# https://wiki.gnome.org/HowDoI/GAction
-# nim c gaction.nim
-import gintro/[gtk, glib, gobject, gio]
-
-proc saveCb(action: SimpleAction; v: Variant) =
-  echo "saveCb"
-
-proc appActivate(app: Application) =
-  let window = newApplicationWindow(app)
-  let action = newSimpleAction("save")
-  discard action.connect("activate", saveCB)
-  window.actionMap.addAction(action)
-  let button = newButton()
-  button.label = "Save"
-  window.add(button)
-  button.setActionName("win.save")
-  var h: cstringArray = allocCstringArray(["<Control><Shift>S"])
-  setAccelsForAction(app, "win.save", h)
-  deallocCStringArray(h)
-  showAll(window)
-
-proc main =
-  let app = newApplication("org.gtk.example")
-  connect(app, "activate", appActivate)
-  discard run(app)
-
-main()