Fix bug with css from other pages being applied

When changing from the index to the examples then back to the index, the
points on the line charts would turn cyan, and the axis lines would be
added back on.

We don't want this happening, and probably don't want it on the examples
pages either, so we clean up the example.css
Merge pull request #60 from tpkelly/gh-pages

Fix bug with css from other pages being applied