texinfo update to 4.13a

[nox@…]

Changes:

• Update to 4.13a.
• Do not depend on lzmautils, use tar.gz archive.
• Install documentation in a versioned directory.

[vinc17@…]

The contents of the 4.13a archive are the same as the 4.13 archive. So, it's better to avoid a rebuild.

Concerning the versioned directory, I don't think it has been decided yet. And there should really be a symlink from a fixed filename, e.g. texinfo -> texinfo-4.13.

[nox@…]

It hasn't, but judging from my own doc/ directory, they are almost all versioned. I'm against a symlink for that as most of our shells have tab completion.

[vinc17@…]

The symlink is still useful if the user wants a symlink to /opt/local/share/doc/texinfo, e.g. to access the files via a web browser or a Finder window (other than /opt/local/share/doc, which has lots of directories) or the Desktop or whatever.