[gnome-panel] bump version to 3.18.0, update NEWS

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 0672f553c8cb9987c9094bc1bde291ce49a74955
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sat Sep 26 07:00:59 2015 +0300

    bump version to 3.18.0, update NEWS

 NEWS         |   13 +++++++++++++
 configure.ac |    6 +++---
 2 files changed, 16 insertions(+), 3 deletions(-)
---
diff --git a/NEWS b/NEWS
index cf9c790..ded029d 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,16 @@
+Version 3.18.0
+==============
+- Added missing icons in menus. (Balló György)
+- Updated libpanel-applet documentation. (Sebastian Geiger)
+- New panel_applet_get_gtk_orientation function in libpanel-applet library.
+  (Sebastian Geiger)
+- Ported away from gnome-common. (Alberts Muktupāvels)
+- Small improvements in themes. (Balló György)
+- Updated translations:
+  Anders Jonsson (sv), Balázs Úr (hu), Daniel Mustieles (es),
+  Josef Andersson (sv), Marek Černocký (cs), Piotr Drąg (pl),
+  Yosef Or Boczko (he).
+
 Version 3.17.2
 ==============
 - Fixes in documentation. (Anders Jonsson)
diff --git a/configure.ac b/configure.ac
index 9398d3d..c302989 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,8 +3,8 @@ dnl Define version info
 dnl **************************************************************************
 
 m4_define([gp_major_version], [3])
-m4_define([gp_minor_version], [17])
-m4_define([gp_micro_version], [2])
+m4_define([gp_minor_version], [18])
+m4_define([gp_micro_version], [0])
 m4_define([gp_version], [gp_major_version.gp_minor_version.gp_micro_version])
 
 dnl **************************************************************************
@@ -58,7 +58,7 @@ AC_SUBST([LIBPANEL_APPLET_API_VERSION])
 LIBPANEL_APPLET_GIR_VERSION=5_0
 AC_SUBST([LIBPANEL_APPLET_GIR_VERSION])
 
-LIB_PANEL_APPLET_LT_VERSION=0:3:0
+LIB_PANEL_APPLET_LT_VERSION=1:0:1
 AC_SUBST(LIB_PANEL_APPLET_LT_VERSION)
 
 AC_ARG_ENABLE([documentation],