Updated xproc/specification repo & wiki

Hi all,

As we discussed, I added a wiki page to the xproc/specification
repository. I think it says the right things, but feel free to edit
it!

I also updated the specification repo so that it builds the XProc
namespace documents.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh
Lead Engineer
MarkLogic Corporation
Phone: +1 512 761 6676
www.marklogic.com