suggested editorial changes for usage guide

Dear all, 
I apologize deeply for only getting to my final review of the Usage
Guide so late. Even worse, my review is not quite finished, and this is
the first email in a short series that will continue through tomorrow.

Attached is an edited source of the Usage Guide which I'd like the
editors to check and commit. In fact, I'll talk to Brahmananda tomorrow
in person so I can make sure that he does it. 8-)

The changes are all intended as editorial, and they go up to the end of
Section 3.6, mostly. I've also removed the change log and editors' to-do
list because they will not be that useful any more.

On top of those changes, the listings 3.4-3, 3.4-4 and 3.4-5 point to
files that contain the content of listings 3.2-3, 3.2-4 and 3.3-2 in
turn, apparently. The links should go to updated files that incorporate
the changes made to the listings in Section 3.4. This is left as-is in
my edited source.

Also, the current source still contains five editor's TODOs which should
either be handled or dropped in the final document.

Best regards,
Jacek