yet another attempt at fixing the timing bug

tests/acceptance/signup_tests.rb

@@ -7,18 +7,19 @@ end
 describe 'signup' do
   include Capybara::DSL
 
-  def wait_for_ajax
-    Timeout.timeout(Capybara.default_wait_time) do
-      loop until page.evaluate_script('jQuery.active').zero?
-    end
-  end
-
   def fill_in_valid
     @site = Fabricate.attributes_for(:site)
-    wait_for_ajax
-    fill_in 'username', with: @site[:username]
-    fill_in 'password', with: @site[:password]
-    fill_in 'email',    with: @site[:email]
+
+    time = Time.now
+    begin
+      fill_in 'username', with: @site[:username]
+      fill_in 'password', with: @site[:password]
+      fill_in 'email',    with: @site[:email]
+    rescue Capybara::ElementNotFound
+      raise if Time.now - time > 30
+      sleep 0.5
+      retry
+    end
   end
 
   def click_signup_button