* gtk/FileChooserDialog.custom : move backend to first param to
avoid conflicts with button names in overloaded ctor.
svn path=/trunk/gtk-sharp/; revision=39856
* gtk/Dialog.custom : add a params array for button info to the ctor.
* gtk/FileChooserDialog.custom : add a params array for button info to
both ctors. Chain them to IntPtr.Zero.
* gtk/Gtk.metadata : hide the ellipsis ctors for the dialog types.
[Fixes#71818]
* sample/GtkDemo/DemoDialog.cs : make the InteractiveDialog use the
new Dialog ctor as it does in the c version.
svn path=/trunk/gtk-sharp/; revision=39713
