Documentation: makeinfo --plaintext

[Akim Demaille]

Hi People!

The documentation does not report --plaintext, and in some places
should probably be updated:

1.3 Output Formats
==================

Here is a brief overview of the output formats currently supported by
Texinfo.

[...]

Plain text
     (Generated via `makeinfo --no-headers'.)  This is almost the same
     as Info output, except the navigational control characters are
     omitted.



I'm surprised to see that --plaintext defaults to output on stdout,
contrary to the other options.  Therefore it ends with:

assignments.texi:7495: avertissement: address@hidden cp' omitted since writing 
to stdout.


Also, it forces --no-split, right?