Demo Portal updates

[Cheetham, Anastasia]

I'm working on FLUID-3728, which involves adding appropriate ARIA, keyboard accessibility, etc. to the demo portal. This has turned into an extensive re-write of the portal code, so
  a) I'm working in a branch, and
  b) I'd love a code review!

The branch is:
    http://source.fluidproject.org/svn/fluid/infusion/branches/FLUID-3728/

I'm not finished yet, but here are some highlights of what I've got implemented so far:

1) The code is updated to make much more use of the framework, including IoC and the new renderer component initializer.
2) The code now loads the HTML for the demo pages from a template, which reduces a *great* deal of duplication, as well as removing lots of hard-coded markup from the JS.
3) The file-type tabs on the right side of each demo now have proper ARIA and are keyboard accessible (using our plugin).
   - there are tests for the ARIA
4) I fixed a CSS bug, so that now the line numbers are actually visible.

NOTE: The code changes are currently only applied to the following demos:
   - keyboard accessibility plugin
   - grid reorderer
   - progress

Also NOTE: I haven't yet fixed up the Code View/Plain View issue that I raised in another email thread, so you'll see both views in the panel, and the links will do nothing.

Final NOTE: The actual keyboard accessibility plugin in this branch is completely broken, so don't expect much :-)


I'd appreciate any thoughts on the direction this is going - good? overkill? have I got the ARIA right? other comments?

Thanks!

-- 
Anastasia Cheetham     Inclusive Design Research Centre
acheetham at ocad.ca            Inclusive Design Institute
                                        OCAD University