gst-discoverer: Support non-ASCII tags

By calling setlocale() to get us multi-byte/UTF-8 support.

https://bugzilla.gnome.org/show_bug.cgi?id=723164

tools/gst-discoverer.c

@@ -21,6 +21,8 @@
 #include "config.h"
 #endif
 
+#include <locale.h>
+
 #include <stdlib.h>
 #include <glib.h>
 #include <gst/gst.h>
@@ -532,6 +534,8 @@ main (int argc, char **argv)
   };
   GOptionContext *ctx;
 
+  setlocale (LC_ALL, "");
+
   ctx =
       g_option_context_new
       ("- discover files synchronously with GstDiscoverer");