RE: RFC 2534 list of ua-media and paper-size values

Here's a cut at vocabulary alignment between HTML and RFC 2534.

HTML screen: arguably the same as RFC2534 screen
HTML tty: no analog; add this to RFC 2534
HTML tv: combines several media features. I suggest changing RFC 2534
         'screen-paged' to add "or which has limited scrolling capabilities"
         to "which cannot scroll", and then defining HTML tv as
         'screen-paged', color=full and some description of
         pix-x & pix-y
HTML projection: is this a kind of 'screen'? Or we should register it? 
HTML handheld: No media feature for "limited bandwidth"; maybe we need
         some feature to describe size in bytes, e.g., 'docsize<2000' ?
         otherwise (small screen, monochrome, bitmapped graphics)
         corresponds to ua-media=screen,pix-x<200,pix-y<200,color=binary
HTML print: sort of like 2534 stationery. In retrospect, I wonder about the
         RFC 2534 distinction with 'transparency', 'envelope', 
         'envelope-plain' is useful. I was trying to be compatible
         with the printer mib, but it's not really "ua-media".
         'continuous' might have been useful for fax if it really
         denoted 'roll paper', but the definition there says
         'continuously connected sheets of opaque material' which
         makes it sound like it's paged.

HTML braille, aural:  these aren't in RFC 2534, and probably should
         be.

If we add 'print', we could eliminate or deprecate 'stationery',
'envelope', 'envelope-plain', 'transparency' and 'continuous' in
favor of recognizing 'print', then the relationship with IPP is
clearer, since most of the IPP media types are a kind of 'print'.

Summary of changes to RFC 2534 UA-Media
    add 'tty'
    modify 'screen-paged' to note "or limited scroll capabilities"
    add 'projection'
    add 'print' as "any kind of printed material".
    deprecate 'continous', 'transparency', 'envelope', and 'envelope-plain';
      note that these are kinds of 'print'. Note that
      continuous rolls might be noted as 'print' with no pix-y limit.
    add 'braille' and 'aural' with the same definitions as in HTML 4.0.

For alignment with IPP, we'll need to update RFC 2534 paper sizes
(mainly adding values), add feature(s) for paper color(ed), and then
describe IPP media primarily as "print". Maybe 'continuous',
'transparency', 'envelope' and 'envelope-plain' are all parts
of some (new) paper-type feature.