[gtkada] Drag and drop

[manuel.op.de.coul at eon-benelux.com]

In the GtkAda 1.2 reference manual for package Gtk.Dnd it says:
"Note that drag-and-drop is currently not supported under Windows 
systems."

To my pleasant surprise though, it works under Windows as well!

I only implemented dragging files and text strings into the main
window of my application. First I was a bit intimidated by the
testgtk code, but this really simple. Make a handler for the
"drag_data_received" signal, connect it to the window, and set
Gtk.Dnd.Dest_Set for it to accept strings and uri-lists. That's all.

A happy New Year to everyone and may the new release come soon!

Manuel