[polari] Bump version to 3.17.91

[Florian Müllner <fmuellner src gnome org>]

commit 166f3922ee6afcbcdafe56789f86c4e1812d80f4
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Sep 2 00:38:25 2015 +0200

    Bump version to 3.17.91
    
    Update NEWS.

 NEWS         |   12 ++++++++++++
 configure.ac |    2 +-
 2 files changed, 13 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index 653f096..205faa4 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,15 @@
+3.17.91 - "Wicked"
+==================
+* Misc. bug fixes and cleanups [Bastian, Florian]
+
+Contributors:
+  Bastian Ilsø, Florian Müllner
+
+Translations:
+  Piotr Drąg [pl], Pedro Albuquerque [pt], Chao-Hsiung Liao [zh_TW],
+  Fran Dieguez [gl], Tom Tryfonidis [el], Yosef Or Boczko [he],
+  Alexandre Franke [fr], Balázs Meskó [hu]
+
 3.17.90 - "Like Kissing the Body Shop"
 ======================================
 * Clear pending messages indication while offline [Florian; #753050]
diff --git a/configure.ac b/configure.ac
index b2f2af5..bc93478 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([polari],[3.17.90],[https://bugzilla.gnome.org/enter_bug.cgi?product=polari],[polari])
+AC_INIT([polari],[3.17.91],[https://bugzilla.gnome.org/enter_bug.cgi?product=polari],[polari])
 
 AC_SUBST([APP_ID],[org.gnome.Polari])