[media] creation of checklist table

Hi all,

As discussed in the last media subgroup phone conference, I have started
creating the table of requirements such that ultimately it can be use to
check against technologies. See
http://www.w3.org/WAI/PF/HTML/wiki/Media_Accessibility_Checklist and feel
free to add your own table underneath by going through the requirements
document at
http://www.w3.org/WAI/PF/HTML/wiki/Media_Accessibility_User_Requirements and
adding the existing requirements.

I believe I have made a start on which technologies are touched by the
different requirements, though it is certainly not complete. Some of the
requirements from the captions section that do not have "cue format" in
their Technologies field should be taken out of that particular table and
moved into their own. Almost all will need to be copied into other sections,
too.

I hope I am not mistaken in thinking that this is taking the first step
towards creating the document that John Foliot has tried to create.

It allows everyone to get involved on the wiki, so please help out in
building some sections - in particular those you care about or have
previously edited.

Cheers,
Silvia.