Twilio Response with arbitrary parameters

gistfile1.rb

{
  AccountSid: AC6c8c88b048a04a173cc629cae521d701
  ApplicationSid: AP6b9619422181dc4e78e2051f4ad126c6
  Caller: client:Anonymous
  CallStatus: ringing
  Called: ''
  To: ''
  foo: bar
  CallSid: CA7fd72394a784f268e0a9bdc251b73204
  From: client:Anonymous
  Direction: inbound
  ApiVersion: '2010-04-01'
  controller: twimlets/voices
  action: agent
  format: xml
}