Add web-safe field slugs

This is sort of a sub-feature request... Maybe even just a suggestion. :)

The idea is that every field has a slug in addition to the name. For example, a field named "Last Name" would auto-create the slug "last-name". The slug would be a field next to name that can be modified, but disallows web-unsafe characters (e.g. spaces). This allows future access to fields such as: %first-name %last-name, which returns a string with that item's first and last name (with a space in the middle).

Anyway, I think you get the idea. It'd just be great to have access to item-specific fields in the future.

Thanks, Podio!