fixes#3724
- provide config.url to the ember client app via a data attribute
- create server and client side helpers to output the URL
- wire up the client side helper
- add a class for testing, and add tests for both the server and client side
fixes#3031
- Adds an initializer for passing config to the frontend, it's not pretty but it works
- Forwards the apps route and hides the apps menu item if apps:true is not present in config.js