This component is used to implement dang sweet buttons.

#### Props

The following props are used to control the display of the component. Any additional props will be passed to the rendered `<a />` or `<button />` element. The presence of a `href` prop determines whether an anchor element is rendered instead of a button.

* `isPrimary`: (bool) whether the button is styled as a primary button.
* `href`: (string) if this property is added, it will use an `a` rather than a `button` element.
