Better SMS validation using AWS pinpoint

[brendanheywood]

https://aws.amazon.com/blogs/messaging-and-targeting/improve-sms-message-delivery-with-phone-number-verify/

https://aws.amazon.com/pinpoint/pricing/

With Phone Number Verify, Amazon Pinpoint checks to see whether the phone number provided is in a valid format based on its country code prefix. If the number is formatted correctly, Amazon Pinpoint leaves the number as the customer entered it. If the number isn’t formatted correctly, Amazon Pinpoint compares the phone number to various rules to make it valid. For example, if a customer enters a leading zero after the country code, Phone Number Verify removes the extra character to make the number valid. In this case, if the customer entered +1 0 206 555 0199 (a United States phone number in the 206 area code), Phone Number Verify changes the number to a correctly formatted number without the extra zero (+1 206 555 0199).