[hitori] build: Use AX_IS_RELEASE

[Philip Withnall <pwithnall src gnome org>]

commit 712afbac3a47d3d5915bae6e67ef087d687d948c
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Wed Mar 11 12:07:44 2015 +0000

    build: Use AX_IS_RELEASE
    
    Check for the presence of a git repository to determine whether things
    like compiler warnings should be fatal. The warnings themselves will be
    hooked up later.
    
    This adds an implicit dependency on autoconf-archive or GNOME’s
    m4-common. These are pulled in by JHBuild, and the relevant macros are
    automatically distributed in tarballs — so the dependencies only need to
    be explicitly installed if you are building from git without using
    JHBuild. This is an unsupported use case.
    
    Note that AC_CONFIG_MACRO_DIR() has already been added to configure.ac.
    
    https://wiki.gnome.org/Projects/GnomeCommon/Migration

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index b29137b..3422927 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,5 @@
 
AC_INIT([Hitori],[3.16.1],[https://bugzilla.gnome.org/enter_bug.cgi?product=hitori],[hitori],[https://wiki.gnome.org/Apps/Hitori])
+AX_IS_RELEASE([git-directory])
 
 AM_INIT_AUTOMAKE([check-news dist-xz no-dist-gzip subdir-objects])
 AC_CONFIG_HEADERS([config.h])