[polari] Bump version to 3.15.91

[Florian Müllner <fmuellner src gnome org>]

commit 52431cd58cea13b8c3ce51642425dcdbaff5c101
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Mar 5 11:53:33 2015 +0100

    Bump version to 3.15.91
    
    Update NEWS.

 NEWS         |   17 +++++++++++++++++
 configure.ac |    2 +-
 2 files changed, 18 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index 0a85d59..36e5973 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,20 @@
+3.15.91 - "I'm buying him a beer"
+=================================
+* Register telepathy service to enable use as default channel handler
+  [Giovanni; #745418, #745499]
+* Misc. bug fixes [Florian; #745203, #743988]
+
+Contributors:
+  Giovanni Campagna, Florian Müllner
+
+Translations:
+  Yosef Or Boczko [he], Stas Solovey [ru], Cheng-Chia Tseng [zh_TW],
+  Daniel Mustieles [es], Tom Tryfonidis [el], Dušan Kazik [sk],
+  Rafael Ferreira [pt_BR], Efstathios Iosifidis [el], Daniel Korostil [uk],
+  Balázs Úr [hu], Matej Urbančič [sl], Alexandre Franke [fr],
+  Fran Dieguez [gl], Milo Casagrande [it], Marek Černocký [cs],
+  Мирослав Николић [sr, sr latin], Piotr Drąg [pl]
+
 3.15.90 - "Plenty of meat, only one potato"
 ===========================================
 * Add high-contrast application icon [Jakub; #735670]
diff --git a/configure.ac b/configure.ac
index b4f5479..777dc3a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([polari],[3.15.90],[https://bugzilla.gnome.org/enter_bug.cgi?product=polari],[polari])
+AC_INIT([polari],[3.15.91],[https://bugzilla.gnome.org/enter_bug.cgi?product=polari],[polari])
 
 AC_SUBST([APP_ID],[org.gnome.Polari])