[glibmm] Require the latest libsigc++

[Murray Cumming <murrayc src gnome org>]

commit a0c02603cc9810e1361f71cb0ad2cb7fc4cf10a4
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Sep 3 18:31:53 2015 +0200

    Require the latest libsigc++
    
    So we can use the trackable move operations.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index bfb3139..0f48daf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -64,7 +64,7 @@ AS_IF([test "x$enable_static" = xyes],
 
 glibreq='2.0 >= 2.45.5'
 
-GLIBMM_MODULES="sigc++-2.0 >= 2.2.10 glib-$glibreq gobject-$glibreq gmodule-$glibreq"
+GLIBMM_MODULES="sigc++-2.0 >= 2.5.4 glib-$glibreq gobject-$glibreq gmodule-$glibreq"
 GIOMM_MODULES="$GLIBMM_MODULES gio-$glibreq"
 test "x$glibmm_host_windows" = xyes || GIOMM_MODULES="$GIOMM_MODULES gio-unix-$glibreq"