Bug#429701: texinfo: inconsistency concerning the number of spaces after a period

[karl@freefriends.org (Karl Berry)]

    > Foo. Bar.
    >
    > Foo.
    > Bar.

I can agree it's a bug, but makeinfo has always simply copied
"intraline" spaces ("Foo. Bar.") as-is, and I, at least, am not likely
to implement anything different in the foreseeable future, if ever.
makeinfo has no real understanding of text at all.  I suppose something
like TeX's spacefactor codes is the most viable approach.

The reason double spaces are assumed/inserted is for support with Emacs
sentence commands, by the way.  Supporting insertion of a single space
after sentences might not be too hard (a lot easier than spacefactors
anyway).

Patches welcome :).