Admin Integration Tab does not account for prefixed store

[onedanshow]

I've got my site namespaced by /store by using

mount Spree::Core::Engine, :at => '/store'

The integration tab doesn't account for this. It's a black page when I first visit it because the Backbone app is looked for "/admin/integration" and not "/store/admin/integration". I have to click one of the menu options to get it going, btu then the URL is set incorrectly by push state and links in this tab don't work because they are missing the "/store"

I'm on the latest commit of the 2-1-stable branch. 813d0a7