Require newer gtk-vnc, to get a known GTK+ 3 version

configure.ac

@@ -76,7 +76,7 @@ GLIB_REQUIRED=2.25.11
 GTK_REQUIRED=2.90.4
 GCONF_REQUIRED=2.16.0
 GTHREAD_REQUIRED=2.0.0
-GTK_VNC_REQUIRED=0.3.10
+GTK_VNC_REQUIRED=0.4.1
 AVAHI_REQUIRED=0.6.26
 PANEL_REQUIRED_VERSION=2.0.0
 TELEPATHY_GLIB_REQUIRED=0.11.6
@@ -115,7 +115,7 @@ AC_SUBST(VINAGRE_CFLAGS)
 AC_SUBST(VINAGRE_LIBS)
 
 PKG_CHECK_MODULES(VNC, \
-  gtk-vnc-1.0 >= $GTK_VNC_REQUIRED \
+  gtk-vnc-2.0 >= $GTK_VNC_REQUIRED \
   gtk+-3.0 >= $GTK_REQUIRED \
   libxml-2.0 >= $XML_REQUIRED
 )