Upgrade to chartjs 2.0.2

[mcmoe]

Instead of forcing the bower dependency to chartjs 1.x.x, I've updated the code to match the latest API changes introduced in the chartjs 2.0 release. I've also enriched the demo with the eight different chart types. While doing so, I found it reasonable to allow declaration of multiple colors.

Extra:

• Support for shadow dom (div wrapper needed on chartjs-element to avoid chartjs error on resize when getting canvas parent)

Resolves issue #4

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