[tei-council] clarifications for WD chapter

[Syd Bauman]

OK, I've wrapped these changes into WD, and generated an HTML
Guidelines for y'all to check out. In particular, see

http://bauman.zapto.org/~syd/temp/Guidelines-web/html/WD.html#D25-20
and
http://bauman.zapto.org/~syd/temp/Guidelines-web/html/WD.html#D25-30

Questions:

* When you (CW & MB) wrote "&#x8AAC;" in the <egXML>, did you want
  the output to show a CJK character or a numeric character
  reference? 

* The last new bit talks about the case where there are two variant
  glyphs, neither of which is defined in Unicode. Should we mention
  that the mechanism discussed is generalizable? I.e. if there are 3
  or more variant glyphs, you do the same thing: define one as a
  <char> and the others as <glyph> variants thereof.