Try to make some sense out of the mess that used to be INSTALL.TXT.

Try to make some sense out of the mess that used to be INSTALL.TXT.

1.  Bring floppies.sgml section in-line into install.sgml, where it
makes more sense.

2.  Slightly reorganize some sections of Installation section and
do some wordsmithing.

3.  Update distribution layout to reflect RELNOTESng and new compat
distributions.

4.  Update upgrade file list from 4-STABLE.

5.  It's been a long time since 2.2.X; get rid of instructions dealing
with "new" handling of compatability slices and fix up other references
in the text.

6.  Hunt down and kill emoticons with extreme prejudice.  Try to
tone down the use of exclamation points.

7.  Cross-reference new and improved Installation chapter in
Handbook.

8.  Add a proper abstract for this document.