module Padrino::Helpers::FormHelpers

def configured_form_builder_class(explicit_builder=nil)

configured_form_builder_class(nil) => StandardFormBuilder
If explicitly defined, returns that, otherwise returns defaults
Returns the FormBuilder class to use based on all available setting sources 
def configured_form_builder_class(explicit_builder=nil)
  default_builder = self.respond_to?(:options) && self.options.default_builder
  configured_builder = explicit_builder || default_builder || 'StandardFormBuilder'
  configured_builder = "Padrino::Helpers::FormBuilder::#{configured_builder}".constantize if configured_builder.is_a?(String)
  configured_builder
end