Implement validation of chart config object prior to rendering

[clhenrick]

As mentioned in a recent PR I'm noticing that we are starting to do some config validation within the components. I think a better way to do this would be either to introduce some static typing system like Flow or at least validate the config object each time setConfig() is called. That way we won't have to worry about whether or not a config property is of a certain type before applying it in a component.