The phone number and zip code validators need improved. Possible features include:
- phone number can negate the accepted area codes, meaning that accept area codes not in list.
- phone number optional; instead of allowing all digits, remove this and only allow properly formatted numbers
- include separate validator to process numeric straight-only values (no formatting such as space or dash)
- figure out how to not to include non-allowed patterns (for instance, US zips don't allow 000)