func WithHistory(history History) func(*Router) error {
	return func(rc *Router) error {
		rc.history = history
		return nil
	}
}
WithHistory is a configuration option to set the history implementation to use.
package grouter
import (
	"github.com/bep/gr"
	"github.com/bep/gr/support"
	"github.com/gopherjs/gopherjs/js"
)
type Router struct {
	*js.Object
	root Route
	history History
}
type History struct {
	*js.Object
}