Blacklists IO::E* classes

I'm removing these for now. Looks like they are dynamically generated and inherit from `Errno::E*` classes that, for whatever reason, are not listed as Ruby core. (It looks like they are generated straight from the C source, but I'll have to research more.) Regenerated all data files in light of this.
Adds chord_layout.js
Adds CSS stylesheets
Adds index.html
Updates README
Tweaks to get as presentable as I can

- Gives the chords a slightly darker color and a fade in/out animation
- Resizes the height/width to 960px
- Shortens the outer radius so that all the text fits nicely
- Hacks tooltip so that it doesn't show 'Array' when not on an arc or chord
- General tidying of chord_layout.js code