Same shortcut as for email addresses, but then for phone_numbers.

[basvodde]

Basically the same as the helper for email_addresses, but then for phone numbers. Next I'd probably want to change the default behavior of some earlier methods, where they earlier returned a nil when not set, it would perhaps be better to return an empty string as it usually makes the code easier when dealing with always a string than dealing with nil. But thats next. This one should be easy.

[lucasmartins]

:+1: Looks nice! Thanks for the code!