[glib] Document that g_list_sort is a stable sort.

[Josselin Mouette <jmouette src gnome org>]

commit ff2f4a12ee673cbb020d44fca2adb81be3c99f49
Author: Josselin Mouette <joss debian org>
Date:   Sun Nov 20 16:53:36 2011 +0100

    Document that g_list_sort is a stable sort.
    
    This is a guarantee for the future so that applications can rely on it.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=531973

 glib/glist.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/glib/glist.c b/glib/glist.c
index 7378c25..dac7dc8 100644
--- a/glib/glist.c
+++ b/glib/glist.c
@@ -1075,7 +1075,8 @@ g_list_sort_real (GList    *list,
  *     first element comes before the second, or a positive value if 
  *     the first element comes after the second.
  *
- * Sorts a #GList using the given comparison function.
+ * Sorts a #GList using the given comparison function. The algorithm 
+ * used is a stable sort.
  *
  * Returns: the start of the sorted #GList
  */