Add JS that toggles class on HTML indicating availability of JS.

[stephaniehobson]

Added to the head to avoid FOUC, just needs to have element to run so doesn't need to wait for DOM ready. Used same class as Bedrock.

[craigcook]

I'm hesitant to add embedded JS. It's justified in this instance but if this is going to evolve into a set of starter templates and markup patterns that serve as examples of best practices, I'm worried about setting a precedent. That could be addressed by documentation, I suppose.

Or we can move it to an external "global.js" file to serve as a starting point for any other global functions someone might want to execute on every page. Of course, moving it external can bring back the FOUC, depending on how the .no-js class gets used.

Or maybe we should just lose the whole .no-js/.js business entirely, at least for this framework. It's a sound methodology when called for, but maybe we just don't need it built into the boilerplate.