Too extreme enhanements

    Various enhancements:

    * Replace Reeder.load! with Lotus::Model#load!
    * Use Lotus::Model DSL for mapping
    * Move mapping to config/mapping
    * Remove Repositories namespace, instead use Reeder namespace
    * Move Reeder::Web route to routes file
    * Create Reeder::Container router
    * Move web under apps/
    * RESTful resource :articles