Allow CDDB track listing to be user-reorderable (by dragging entries up/down)
like it was in GTK1 version.

diff -X dontdiff-easytag -urNp easytag-0.31/src/cddb.c easytag-dsd/src/cddb.c
--- easytag-0.31/src/cddb.c	2004-06-29 12:06:28.666910608 +0100
+++ easytag-dsd/src/cddb.c	2004-06-29 12:11:31.652849744 +0100
@@ -504,8 +504,7 @@ void Open_Cddb_Window (void)
                                                       renderer, "text", CDDB_TRACK_LIST_TIME, NULL);
     gtk_tree_view_append_column(GTK_TREE_VIEW(CddbTrackListView), column);
 
-    gtk_tree_sortable_set_sort_column_id(GTK_TREE_SORTABLE(CddbTrackListModel), SORT_LIST_NUMBER, GTK_SORT_ASCENDING);
-
+    gtk_tree_view_set_reorderable(GTK_TREE_VIEW(CddbTrackListView), TRUE);
     gtk_container_add(GTK_CONTAINER(ScrollWindow),CddbTrackListView);
     gtk_tree_selection_set_mode(gtk_tree_view_get_selection(GTK_TREE_VIEW(CddbTrackListView)),
                                 GTK_SELECTION_MULTIPLE);