[html-formfu] Very similar forms for edit and add

[Alex Povolotsky]

Hello!

I'm writing (yet annother) CRUD controller, and I need two very similar 
forms, for add and edit a user.

On adding user, I'd like to set password field required; for editing, 
it's not, and empty password field means "password unchanged".

What's the best way to implement this functionality without having two 
similar config files?

Alex.