[rfc-i] Updated rfc macros

[blilly at erols.com (Bruce Lilly)]

There's been another update to draft-lilly-using-troff; currently at -04.

Testing with plan 9 preprocessors and formatters was rather depressing:
o "nroff" is just a wrapper for "troff -N"; it doesn't handle form feeds
  well.
o grap generates pic with labels in a 0.25 inch box, which isn't a suitable
  dimension for text output (not a multiple of 1/6 inch line spacing).
o pic handles multi-line text poorly.
o tbl uses underscores for horizontal rules in text, with overstriking of
  text.  Looks nice in table headings, but awful within tables. Oddly,
  Postscript output table rules are comprised of text characters.
o generated postscript (requiring two postprocessors) is bulky and has no
  hints suitable for repaginating Table of Contents.

I made some changes to the macros and postprocessor scripts to mitigate
problems, but (other than dformat and eqn) the plan 9 implementation
doesn't seem suitable for generating I-D/RFC text or PostScript.

If anybody has access to a DWB-derived implementation, I'd appreciate
feedback (either here or off-list) regarding how well that works.

HTML (not an official I-D/RFC format) has been improved.  Table of contents
entries/section headings, reference citations, and URIs are hyperlinked.
Unofficial copies of the draft in various formats are available at
http://users.erols.com/blilly/Internet-Drafts.

Future plans:
o add ability to specify text indent in variable lists and number lists
o pdfmark entries in PostScript output for PDF bookmarks and hyperlinks