Version numbers in PDF of manual

[Rik]

jwe,

The PDF is showing "March 2018" as the publication date.

It seems that we simply haven't transitioned the file octave.texi to use
the variables in the file version-octave.texi (auto-generated).

The file version-octave.texi has these variables:

@set UPDATED 10 April 2018
@set UPDATED-MONTH April 2018
@set EDITION 4.3.90
@set VERSION 4.3.90

The title page for the Octave manual in octave.texi has

@titlepage
@title GNU Octave
@subtitle A high-level interactive language for numerical computations
@subtitle Edition 4 for Octave version @value{VERSION}
@subtitle March 2018
@sp 2
@multitable @columnfractions 0.4 0.025 0.65
@item
@flushright @image{octave_logo,2.1in}
@end flushright
@tab
@c this is a spacer column
@tab
@sp 8
@titlefont{Free Your Numbers}
@end multitable
@author John W. Eaton
@author David Bateman
@author address@hidden Hauberg
@author Rik Wehbring
@page
@vskip 0pt plus 1filll
Copyright @copyright{} 1996, 1997, 1999, 2000, 2001, 2002, 2005, 2006,
2007, 2011, 2013, 2015, 2016, 2017, 2018 John W. Eaton.

This is the fourth edition of the Octave documentation, and is consistent
with version @value{VERSION} of Octave.

It seems like the right thing to do is to use these variables in
octave.texi so that the documentation automatically follows the build.

I made that change here
(http://hg.savannah.gnu.org/hgweb/octave/rev/5cdd48b2d9ca).

--Rik