Techniques branches updated

We ran into a problem making pull requests from the techniques branches, 
because of the way I had set them up. I've fixed them, which required 
syncing them with the master branch, so they now have all the files, not 
just the lone technique file. It seems this will be necessary for pull 
requests to work, so we can't have the "here's a simple branch to work 
in" approach.

If you are working in a clone or fork, you will need to update. You'll 
need to look a little harder for the technique file to edit, but the 
process is otherwise the same as previously described. Because new 
techniques have a temp filename, they should be easy to tell apart from 
the other techniques which have ID filenames. IDs are assigned by chairs 
and files renamed *after* the WG accepts a new technique.

Remember, this is now all in the wcag repository: 
https://github.com/w3c/wcag/

Michael