Some tests for users controller, and fixed users#index

spec/support/sigin_macros.rb

@@ -0,0 +1,10 @@
+
+module SigninMacros
+  def sign_in(user)
+    visit new_user_session_path
+    fill_in 'user_email', with:'user.email'
+    fill_in 'user_password', with: 'user.password'
+    click_button 'Sign in'
+    page.should have_content('Signed in successfully')
+  end
+end