New introduction for PDF Technology section

Mary, following discussion during today's teleconference, could you change
the introduction of the PDF Technology section to read:

The Portable Document Format (PDF) is a file format for representing
documents in a manner independent of the application software, hardware, and
operating system used to create them, as well as of the output device on
which they are to be displayed or printed. PDF files specify the appearance
of pages in a document in a reliable, device-independent manner. The PDF
specification was introduced by Adobe Systems in 1993 as a publicly
available standard.  In January 2008, PDF 1.7 became an ISO standard (ISO
32000-1).

Of note for accessibility is PDF/UA (Universal Accessibility) which became
an ISO Draft International Standard (DIS) in November 2010 (ISO/DIS
14289-1). (See PDF/UA Wiki (ISO DIS 14289 - 1).) The scope of PDF/UA is not
meant to be a techniques (how-to) specification, but rather a set of
guidelines for creating accessible PDF. The specification describes the
required and prohibited components and the conditions governing their
inclusion in or exclusion from a PDF file in order for the file to be
available to the widest possible audience, including those with
disabilities. The mechanisms for including the components in the PDF stream
are left to the discretion of the individual developer, PDF generator, or
PDF viewing agent. PDF/UA also specifies the rules governing the behavior
for a conforming reader.