[gnome-tetravex] Depend on unreleased Vala 0.23

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 4853c2132da1f89272725f27fcb1b62f0bc0956f
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Mon Nov 25 12:59:39 2013 -0600

    Depend on unreleased Vala 0.23
    
    For GTK+ 3.11.2 bindings. Vala is optional except when generating
    tarballs.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index f8ba15e..053158c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -4,7 +4,7 @@ AM_SILENT_RULES([yes])
 AM_MAINTAINER_MODE
 GNOME_MAINTAINER_MODE_DEFINES
 
-AM_PROG_VALAC([0.16.0])
+AM_PROG_VALAC([0.23])
 AM_PROG_CC_C_O
 
 GLIB_GSETTINGS