AV Payment Gateway

• Initialize transaction
• Payment gateway (Braintree)
• Check status
• Process order
  Complete waiting transaction
• Cancel transaction
• Update store status
  Acts as a callback to store and returns whatever is provided in returnStatus parameter
• Update status
  Force status update on AVPG (for MegaPos or Quipu).
  NOTE that it then automatically also updates store status!
  Check status already updates status but in case of errors that is not the case so we have this to enable missed calls or communications glitches betwen AVPG and Service Provider