Error in router

[Lin]

Removing singleton fixes the problem

[error] #PID<0.338.0> running Store.Endpoint terminated
Server: localhost:4000 (http)
Request: GET /
** (exit) an exception was raised:
    ** (FunctionClauseError) no function clause matching in Store.Router.Helpers.checkout_path/2

Any idea why?

[Joshua Nussbaum]

@Immortalin looks like the last PR was missing some changes. I've fixed it in master.