pbd spec v1r1 - Fred's revisions

Attached are some additional suggested edits to section 2 and 4, including:

1.      
Revision to text of introduction and section 1.5 (definition of personal data)

2.      
Minor tweaks to wording of section 2 and 4

3.      
Added new Section 6: Conformance

These suggested edits will be included in the master chart.

Thx, Fred