build admin system...
Merge branch 'master' of http://github.com/SungHong-Cho/kidspark

Conflicts:
	app/assets/javascripts/update_latest_photos.js.erb
	app/controllers/users_controller.rb
	app/models/user.rb
	log
add admin log in & log out, link to photos/destory at each photo_boxes at photos/index.html if admin logined