Adjusted signup BAN delay when fixing form

If a user filled a form, missed a field, and
corrected the mistake too quickly, they could
be banned. So we keep the timestamp of the original
form during the subsequent renders of the form.

BrainPortal/app/controllers/signups_controller.rb

@@ -63,7 +63,9 @@ def create #:nodoc:
       return
     end
 
+    # Validation failed, return to form
     if ! @signup.save
+      @auth_spec = form_generated_at_int # keep old form_generated time
       render :action => :new
       return
     end

BrainPortal/app/views/signups/new.html.erb

@@ -26,7 +26,7 @@
 
 <%= form_for @signup, :url => {:action => (@signup.new_record? ? "create" : "update"), :id => @signup.id} do |f| %>
   <%= error_messages_for @signup %>
-  <%= hidden_field_tag :auth_spec, Time.now.to_i.to_s %>
+  <%= hidden_field_tag(:auth_spec, (@auth_spec.to_s || Time.now.to_i.to_s)) %>
 
   <div class="generalbox">
     <p class="warning"> Fields with an asterisk (*) are mandatory.</p>