Gtk: Regenerate .defs and .xml
Entry: Add get/set_tabs() and property.
Label: Add get/set_lines() and property.
Widget: Add drag_begin() that takes x and y coordinates.

* gtk/src/widget.hg: Wrap gtk_drag_begin_with_coordinates().
Widget: add get_scale_factor().
Gdk: Regenerate .defs and .xml
Gdk: Cursor: Wrap some new functions.

* gdk/src/cursor.hg: Add create() that takes a Surface,
  and get_surface().
Button: Add constructor that takes an icon_name and size.

* gtk/src/button.[hg|ccg]: Reimplement to match the new
  gtk_button_new_from_icon_name() function.