Log Message:
Updated gtexinfo to 6.3.

6.3 (10 September 2016)

* Language:
  . The commands `@setcontentsaftertitlepage' and
    `@setshortcontentsaftertitlepage' have been removed.
  . @-commands are no longer supported within `@errormsg'.

* texinfo.tex:
  . For a couple of characters (opening and closing braces), use glyphs
    from the standard TeX math fonts instead of using EC fonts which are
    less likely to be installed.
  . Use of user-defined macros in the text of an index entry is more
    reliable when the text contains Texinfo @-commands.
  . @synindex and @syncodeindex have been fixed (broken in the last
    release).
  . Support added for native UTF-8 support with XeTeX and LuaTeX.
  . Support of PDF output with XeTeX improved.
  . You can use a new file doc/texinfo-ja.tex for Texinfo documents in
    Japanese.  doc/short-sample-ja.tex is a sample document.  New
    support file doc/txi-ja.tex for Japanese.

* texi2any:
  . Fix handling of compiler options when building Perl extension modules.

* texi2dvi:
  . Can now process files whose absolute paths contain space characters,
    as long a relative path to the file is given.  Better support of
    files with unusual characters in their names.
  . No longer exits prematurely in some circumstances (due to the script
    running under "set -e").
  . Bug fixed which made the `--command' and `--tidy' options
    incompatible.

* info:
  . Handling of "invalid" value in infokey file fixed.

6.2 (withdrawn)