implement openID authentication

app/views/devise/shared/_links.erb

@@ -0,0 +1,19 @@
+<%- if controller_name != 'sessions' %>
+  <%= link_to "Sign in", new_user_session_path %><br />
+<% end -%>
+
+<%- if devise_mapping.registerable? && controller_name != 'registrations' %>
+  <%= link_to "Sign up", new_registration_path(resource_name) %><br />
+<% end -%>
+
+<%- if devise_mapping.recoverable? && controller_name != 'passwords' && controller_name != 'registrations' %>
+  <%= link_to "Forgot your password?", new_password_path(resource_name) %><br />
+<% end -%>
+
+<%- if devise_mapping.confirmable? && controller_name != 'confirmations' %>
+  <%= link_to "Didn't receive confirmation instructions?", new_confirmation_path(resource_name) %><br />
+<% end -%>
+
+<%- if devise_mapping.lockable? && resource_class.unlock_strategy_enabled?(:email) && controller_name != 'unlocks' %>
+  <%= link_to "Didn't receive unlock instructions?", new_unlock_path(resource_name) %><br />
+<% end -%>

app/views/devise/shared/_openid.html.haml

@@ -0,0 +1,4 @@
+- if devise_mapping.omniauthable?
+  - resource_class.omniauth_providers.each do |provider|
+    = link_to image_tag("#{provider}.png", size: '32x32') + provider , omniauth_authorize_path(resource_name, provider)
+    %br