Drop redirect within form validation

Problem/Motivation

There is a redirect within the form validation which has undesired side-effects. Namely when the form does not validate for annonymous users it will not present them with the standard spamicide error message because the code redirects them to the form page.

Steps to reproduce

1. Fill a form completely, including the "feed_me" field as annonymous user
2. Notice that there is no error message and the user gets redirected to the empty form

Proposed resolution

I propose removing the redirect code so that the form can properly report error messages.

Remaining tasks

None

User interface changes

None

API changes

None

Data model changes

None