Data Sanitization

[carldanley]

I ran into an interesting problem tonight with the signature data for petition ID: 50cac54dc988d4d27b00000b. You can view the data here: https://api.whitehouse.gov/v1/petitions/50cac54dc988d4d27b00000b/signatures.json?limit=1000&offset=0

This led me to reviewing other zip code entries and finding other pieces of unsanitized data. I am proposing that you enforce sanitization on API entries, especially the zip code field.

[carldanley]

Also, they need to be validated against US zip codes as well. I see various 6 digit zip codes, etc.