drwho.tex: Put the companion tracks /exactly/ in the centre of the page.

My new printer unexpectedly printed this in duplex mode, which was fine;
but it caused me to notice that the companion tracks very nearly, but
not quite, ran down the midline of the page.  Fix it so that they're
exactly in the middle.

diff --git a/drwho.tex b/drwho.tex
index 3b53aa7..af01a1b 100644 (file)
--- a/drwho.tex
+++ b/drwho.tex
@@ -30,7 +30,7 @@
 \voffset=-1in \topmargin=20mm \headheight=0mm \headsep=0mm
 \textheight=\paperheight \advance\textheight by -2\topmargin
 
-\newdimen\titlewidth \titlewidth=70mm
+\newdimen\titlewidth \titlewidth=0.5\textwidth \advance\titlewidth by -40pt
 
 \pagestyle{empty}
 \errorcontextlines=50