Local.config should not include file attribute.
Local.config should not include file attribute.

This looks like it was copy/pasted out of Web.config. Proposed change will allow it to work. Also suggest changing from angle brackets to square brackets for the your-ngrok-subdomain setting to not throw off VS formatting.
TwilioDevEd/clicktocall-csharp,TwilioDevEd/clicktocall-csharp,TwilioDevEd/clicktocall-mvc4,TwilioDevEd/clicktocall-csharp,TwilioDevEd/clicktocall-mvc4