Updated the PWP Draft

As mentioned on the call last Monday, I have updated the editor's draft for PWP on the repo:

http://w3c.github.io/dpub-pwp/

The main changes are:

- removed the use cases (they should migrate to the UCR documents) to make the draft more tech oriented
- merged with the document produced by the locator TF

Cheers

Ivan

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Ivan Herman, W3C
Digital Publishing Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
ORCID ID: http://orcid.org/0000-0003-0782-2704