UI freezes on OTP request timeout

[binh-dam-ibigroup]

On deployments that use OTP Middleware, performing an itinerary search such as this one causes a UI freeze after some itinerary results are initially displayed. The server (OTP-middleware) logs show a timeout issue, and returns a 500 error to the UI. The UI or the backend should handle such situations gracefully instead of freezing.

[landonreed]

I believe this was resolved within @evansiroky's #230.

[binh-dam-ibigroup]

This issue was still visible last week with the query indicated.