[glib] Mention thread API changes in README

[Ryan Lortie <ryanl src gnome org>]

commit a6da2b9ff91f0b8782a243e342e17a0ace415c11
Author: Ryan Lortie <desrt desrt ca>
Date:   Fri Oct 14 21:52:36 2011 -0400

    Mention thread API changes in README

 README.in |   13 +++++++++++--
 1 files changed, 11 insertions(+), 2 deletions(-)
---
diff --git a/README.in b/README.in
index beeefed..b85a6e9 100644
--- a/README.in
+++ b/README.in
@@ -28,7 +28,17 @@ Notes about GLib 2.32
 =====================
 
 * It is no longer necessary to use g_thread_init() or to link against
-  libgthread.  libglib is now always thread-enabled.
+  libgthread.  libglib is now always thread-enabled.  Custom thread
+  system implementations are no longer supported (including errorcheck
+  mutexes).
+
+* The thread and synchronisation APIs have been updated.
+  GMutex and GCond can be statically allocated without explicit
+  initialisation, as can new types GRWLock and GRecMutex.  The
+  GStatic_______ variants of these types have been deprecated.  GPrivate
+  can also be statically allocated and has a nicer API (deprecating
+  GStaticPrivate).  Finally, g_thread_create() has been replaced with a
+  substantially simplified g_thread_new().
 
 * The g_once_init_enter()/_leave() functions have been replaced with
   macros that allow for a pointer to any gsize-sized object, not just a
@@ -38,7 +48,6 @@ Notes about GLib 2.32
 
 * It is now mandatory to include glib.h instead of individual headers.
 
-
 Notes about GLib 2.30
 =====================