Casper for Halo

Casper theme in Thymeleaf for Halo.

It requires following static variables:

• Map : options - System config
• Map : settings - Current theme config
• List<MenuDTO> : menus - Navigation list
• User : user - Blog owner

For i18n, use #themes.code(messageKey) to get localed message defined in i18n/i18n_xx.properties.