[tei-council] Styling of TEI <ident> in HTML Guidelines

[Syd Bauman]

While I'm super glad this is being done -- it is so oviously, at
least to me, the right thing to do -- it does seem like too little
too late. It would have been very nice to have these contraints in
place over the past two years.

It would probably also make sense to constrain the scheme= attributes
of <gi> and <att>.


Counts of occurences:

   2   <att scheme='HORSE'>
   1   <att scheme='RNGANN'>
   3   <att scheme='XHTML'>
   2   <att scheme='XI'>
   3   <att scheme='XML'>
   1   <att scheme='extreme'>
   8   <att scheme='imaginary'>

   1   <gi scheme='DBK'>
   1   <gi scheme='SMIL'>
   1   <gi scheme='SVG'>
   2   <gi scheme='extreme'>
  77   <gi scheme='imaginary'>


  21   <altIdent type='FPI'>

   8   <biblScope type='chap'>
  44   <biblScope type='issue'>
   1   <biblScope type='note'>
  30   <biblScope type='part'>
 125   <biblScope type='pp'>
  71   <biblScope type='vol'>

  44   <classSpec type='atts'>
 109   <classSpec type='model'>

   1   <div type='Dedication'>
   1   <div type='Preface'>
  35   <div type='div1'>
 154   <div type='div2'>
 237   <div type='div3'>
  75   <div type='div4'>
   1   <div type='titlePageVerso'>

   1   <divGen type='attclasscat'>
   1   <divGen type='elementcat'>
   1   <divGen type='macrocat'>
   1   <divGen type='modelclasscat'>
   1   <divGen type='toc'>

 345   <ident type='class'>
  14   <ident type='datatype'>
  22   <ident type='file'>
   4   <ident type='frag'>
   2   <ident type='ge'>
   4   <ident type='macro'>
  66   <ident type='module'>
   5   <ident type='ns'>
  11   <ident type='pe'>
   2   <ident type='rng'>
   7   <ident type='schema'>

  23   <idno type='doi'>
   2   <idno type='handle'>
   1   <idno type='isbn'>
   2   <idno type='tei'>
 117   <idno type='url'>
  49   <list type='bullets'>
  54   <list type='gloss'>
  25   <list type='ordered'>
  27   <list type='simple'>

  21   <macroSpec type='dt'>
   7   <macroSpec type='pe'>

   1   <moduleSpec type='core'>

   1   <name type='class'>
   5   <name type='datatype'>
   1   <name type='organization'>
  38   <name type='xpscheme'>

  35   <ptr type='cit'>
  23   <ptr type='div1'>
  56   <ptr type='div2'>
  66   <ptr type='div3'>

   1   <relatedItem type='original'>

  12   <title type='main'>
   1   <title type='sub'>
  11   <title type='subordinate'>

   1   <titlePart type='main'>

  51   <valList type='closed'>
  29   <valList type='open'>
  29   <valList type='semi'>