adding first draft of accessibility guidelines

Here and throughout the file, the highlighting doesn't seem to work when viewing : https://github.com/kllevin/westfield_code_guidelines/blob/accessibility/accessibility-guidelines/index.md
Also the images are broken? Am I viewing this wrong? It looks like:
screen shot
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![screen shot 2014-12-30 at 4 25 52 pm](https://cloud.githubusercontent.com/assets/1790763/5584400/96f2d88c-9040-11e4-92d2-c90a79337ff6.png)