Pass TwiML with Call Initiation Requests

The Programmable Voice Calls REST API now accepts TwiML when making outbound calls. Prior to this change, you were required to provide an absolute URL that Twilio would use to retrieve TwiML from your application. This change allows you to provide TwiML instructions when initiating a call with the REST API so that when the call is answered, Twilio immediately starts executing the TwiML instructions. This reduces webhook related delays and provides a simplified call set up mechanism. For more details on passing TwiML when launching an outbound call, check out How To Make Outbound Phone Calls.