Remove query params when using Stagecraft API

When we pass a path onto Stagecraft to find out information about a dashboard, we don't want to include any query parameters because this will cause Stagecraft to return a 404.

@easternbloc, I'd appreciate your feedback on this. The code works but there's a test failure because the test file is in `shared/` and Phantom doesn't know what to do with the `url` module I've required. What's the best way to sort this? Is it to move that test file into `server-pure` and make it work?