add PhoneNumberVerificationRequest class so that responses to callerID POSTs are instantiated as the correctly named object
add PhoneNumberVerificationRequest class so that responses to callerID POSTs are instantiated as the correctly named object

imranraja85/twilio-ruby,philnash/twilio-ruby,twilio/twilio-ruby,dddaisuke/twilio-ruby,sai43/twilio-ruby,MadBomber/twilio-ruby,xeron/twilio-ruby,dattyle/twilio-ruby,mypizza/twilio-ruby-private,jarodreyes/twilio-ruby,hzchirs/twilio-ruby,ShanaLMoore/Magic-8-text,ashleydonohoe/twilio-ruby,eloyesp/twilio-ruby