Naf_Validator: Validate user data with the filter extension

This class can be used to validate data based on rules verified by the filter extension.

It can define a set of validation rules to check values passed in an associative array for instance from $_POST or $_GET.

The class can verify the defined rules using the PHP filter extension.

When a validation rules is not satisfied the class returns a validation result object that can provide more details about the failed rule.