Added support for auto-incorporation of mainline aria spec references

I have checked in a new script (ariaChild.js) and the main json file
(roleInfo.js) so that the dpub.html file can now inherit stuff from the
mainline aria spec.  As the aria spec evolves, we will need to continue to
update the roleInfo.js file but for now we have something we can work with.

Editors, please check github for information on this.  You will need to
roll up your changes into master (or roll down the master changes into your
branch) so that you can see the effects.  Note that there were a couple of
minor changes made to dpub.html as part of the pull request / merge I did
into master so that it would just work.

Let me know if 1) it sucks, 2) it is broken, or 3) you have any questions.

-- 
Shane McCarron
Managing Director, Applied Testing and Technology, Inc.