add cucumber for integration testing and add a feature for statistics

refactor some stuff to support testing statistisc

features/step_definitions/login_steps.rb

@@ -0,0 +1,9 @@
+Given /^I am logged in$/ do
+  @current_user = User.create!(:login => "testuser", :password => "secret", :password_confirmation => "secret")
+  @current_user.create_preference
+  visit login_path
+  fill_in "login", :with => "testuser"
+  fill_in "password", :with => "secret"
+  click_button "Sign in"
+  response.body.should =~ /Login successful/m
+end