fix for omniauth 0.2.0

lib/devise/omniauth.rb

@@ -11,6 +11,7 @@ module OmniAuth
     def initialize(app, name, *args)
       @app = app
       @name = name.to_sym
+      @options = args.last.is_a?(Hash) ? args.pop : {}
       yield self if block_given?
     end
 
@@ -43,4 +44,4 @@ module Devise
         :test_mode!, :stub!, :reset_stubs!, :to => "Devise::OmniAuth::TestHelpers"
     end
   end
-end
+end