DO NOT MERGE YET: Demo site V2

Looking for team feedback (copy, angular.js optimization) for the V2 style guide demo site. (rackerlabs.github.io/encore-ui/)

Going to continue submitting commits, especially those marked FIXME.
I like that you included these in the demo, but at the same time I think the fact that they're aligned differently isn't explained very well and could potentially be confusing to people new to Encore, and possibly look like an error. I think explaining `.page-actions` and how it's used should happen somewhere. Even if it isn't on this button page, it could be linked to.