Make page&screen shot on cuke failure

cukes.diff

diff --git a/features/support/env.rb b/features/support/env.rb
index c26248a..d461a01 100644
--- a/features/support/env.rb
+++ b/features/support/env.rb
@@ -76,3 +76,17 @@ Before do |scenario|
   # Reset overridden settings
   AppConfig.reset_dynamic!
 end
+
+Cucumber::Formatter::LegacyApi::Ast::StepInvocation.class_eval do
+  alias_method :orig_accept, :accept
+
+  def accept formatter
+    orig_accept(formatter)
+    if status == :failed
+      formatter.runtime.support_code.ruby.current_world.instance_eval do
+        save_page
+        save_screenshot
+      end
+    end
+  end
+end