[mutter] Bump version to 3.23.91

[Florian Müllner <fmuellner src gnome org>]

commit 89871e04aa2688131a02f67c18a823cc0e2c56e6
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Mar 1 15:16:19 2017 +0100

    Bump version to 3.23.91
    
    Update NEWS.

 NEWS         |   19 +++++++++++++++++++
 configure.ac |    2 +-
 2 files changed, 20 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index 80b0107..d96c2ed 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,22 @@
+3.23.91
+=======
+* Give libinput read-only access to /sys [Carlos; #778472]
+* Allow edge-scrolling without 2-finger-scroll capable devices [Rui; #778554]
+* Fullscreen windows on the requested monitor on wayland [Rui; #772525]
+* Implement threaded swap_event fallback for NVIDIA driver [Owen; #779039]
+* Avoid pixel conversions when storing textures from cairo [Carlos; #779234]
+* Misc. bug fixes [Piotr, Rui, Florian; #772218, #776919, #778831, #642652]
+
+Contributors:
+  Piotr Drąg, Carlos Garnacho, Rui Matos, Florian Müllner, Owen W. Taylor
+
+Translations:
+  Inaki Larranaga Murgoitio [eu], Daniel Mustieles [es], Claude Paroz [fr],
+  Mario Blättermann [de], Kjartan Maraas [nb], Piotr Drąg [pl],
+  Andika Triwidada [id], Anders Jonsson [sv], Milo Casagrande [it],
+  Fabio Tomat [fur], Rafael Fontenelle [pt_BR],
+  Мирослав Николић [sr, sr@latin], Balázs Meskó [hu], Chao-Hsiung Liao [zh_TW]
+
 3.23.90
 =======
 * Fix window menu placement with HiDPI [Jonas; #776055]
diff --git a/configure.ac b/configure.ac
index 5a935ee..d200083 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,7 +2,7 @@ AC_PREREQ(2.62)
 
 m4_define([mutter_major_version], [3])
 m4_define([mutter_minor_version], [23])
-m4_define([mutter_micro_version], [90])
+m4_define([mutter_micro_version], [91])
 
 m4_define([mutter_version],
           [mutter_major_version.mutter_minor_version.mutter_micro_version])