Update libsndfile to 1.0.29pre2+git

This pulls in MANY (over 890) changes compared to our
from our current 1.0.24 version.

lib-src/libsndfile/src/test_binheader_writef.c

@@ -0,0 +1,61 @@
+/*
+** Copyright (C) 2017 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU Lesser General Public License as published by
+** the Free Software Foundation; either version 2.1 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU Lesser General Public License for more details.
+**
+** You should have received a copy of the GNU Lesser General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include "sfconfig.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <errno.h>
+
+#include "common.h"
+
+#include "test_main.h"
+
+void
+test_binheader_writef (void)
+{	char buffer [18] ;
+	SF_PRIVATE	sf_private, *psf ;
+	int			k, errors = 0 ;
+
+	print_test_name ("Testing binheader_writef") ;
+
+	memset (&sf_private, 0, sizeof (sf_private)) ;
+
+	psf = &sf_private ;
+	for (k = 0 ; errors == 0 && k < 10 ; k++)
+	{	psf_strlcpy (buffer, sizeof (buffer), "abcdefghijklmnop") ;
+		buffer [k] = 0 ;
+
+		psf_binheader_writef (psf, "Ep", BHWp (buffer)) ;
+
+		if ((psf->header.indx & 1) != 0)
+			errors = 1 ;
+		} ;
+
+	free (psf->header.ptr) ;
+
+	if (errors)
+	{	puts ("\nExiting due to errors.\n") ;
+		exit (1) ;
+		} ;
+
+	puts ("ok") ;
+} /* test_log_printf */
+