Slide deck for Silver Prototypes

Please look at our latest slides about the Silver prototypes. For those 
who are not active in  Silver at the moment, this is a good way to catch 
up on the work we have done in the last 6 months since the Design Sprint.

Luis and I took the slide deck we did for TPAC presentation to the 
Accessibility Guidelines working group and updated it:

  * Removed the very W3C-specific slides that didn't apply to a general
    "accessibility conference" audience.
  * Added new slides to explain the Conformance prototype work we did at
    TPAC.
  * Added extensive speaker notes for each slide to help explain it to
    someone who isn't hearing a presentation.

https://docs.google.com/presentation/d/1YGwCbQ1xXILFihGl4YzHuvmiheDxtkge5V7fD7-t_sM/edit#slide=id.g4672a50df4_0_133

The permissions are set so anyone can view and comment on the slide 
deck.  Please feel free to add comments.  Please feel free to use this 
slide deck if you are doing a presentation and want to include 
information on Silver.

I'm very excited about the new Conformance work and am looking forward 
to talking about it in more detail at the Tuesday meeting.  Luis and I 
used this slide deck for A11yBOS conference presentation on 27 October, 
and had good questions and feedback.

jeanne