[wsrp-wsia] [change request #241] Drop "user-facing"

Document: Spec

Sections: 1 & 1.2

Requested by: Alejandro Abdelnur

Old text: "user-facing web services"

New text: "web services"

Reasoning: There is not such a thing as "user-facing" web services.
They produce information that will be presented to a user but that is the
case for many web services. And the client (consumer) will have to do more
or less transformations to display this information to the user.