[gnome-sudoku] Require Gtk+ 3.15.0.

[Arnaud Bonatti <arnaudb src gnome org>]

commit 38134c12fcc9515d0ea2b35443a617d8bd4e02a6
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Oct 24 12:54:03 2014 +0200

    Require Gtk+ 3.15.0.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index c3c05b4..0a87073 100644
--- a/configure.ac
+++ b/configure.ac
@@ -24,7 +24,7 @@ dnl Dependencies
 dnl ###########################################################################
 
 GLIB_REQUIRED=2.40.0
-GTK_REQUIRED=3.13.4
+GTK_REQUIRED=3.15.0
 QQWING_REQUIRED=1.2.0
 
 PKG_CHECK_MODULES(GNOME_SUDOKU, [