Primer WD approved

Hi all,

The WG approved pushing out the latest RDFa Primer as a WD, which means 
we'll have a consistent Primer-and-Syntax, and we can now focus on the 
(hopefully) last draft of the Primer with the edits we really want to make.

I'll take a pass at this soon, taking into account Manu and Mark's 
comments. I hope to get everyone's help on this, since this will likely 
be the first doc that people read when they google "RDFa" (that is, 
until we get our awesome community site going.... CC is working on the 
wiki install.)

-Ben