[Groff] .AU, .AB a bit off-center in -Thtml output

[Dorai Sitaram]

When converting an ms document to html using -Thtml,
the .TL comes out centered, but all the other things
that go with the title, such as .AU, .AB, are
noticeably to the right.

This is because these seem to be centered in the
second column of a table whose first column is 8% wide
and whose second column is 92% wide.  There seems to be
no need for a two-column table here, and it's spoiling
the centering.

Example, create a file j.ms with the following
contents:

.TL
title
.AU
author
.AB no
.AE
.LP
Ok, let's see how centered it is.
.ex

and do

groff -ms -Thtml j.ms > j.html