[ac] Update to Access Control Draft

Given I merged 4 distinct documents, some editorial review would be 
appreciated. 

Anne, I changed "Web Page" to "Web Document" in the title as at least 
for me, web page means HTML and web document means any kind of 
resource.  If I'm the only one who has this mental model, I am happy to 
change it back.

Dean, should I add you to the list of editors?

Brad