Corrections in SchedulesController

- Controler file name pluralized
- Load and authorization fixed and improved
- Consider that save can fail in create action
- Eliminate unnecessary if in update action
- Ability and tests related to the schedules link in the admin sidebar fixed

config/routes.rb

@@ -22,7 +22,7 @@ Osem::Application.routes.draw do
     resources :comments, only: [:index]
     resources :conference do
       resource :contact, except: [:index, :new, :create, :show, :destroy]
-      resources :schedule, only: [:index, :create, :show, :update, :destroy]
+      resources :schedules, only: [:index, :create, :show, :update, :destroy]
       resources :event_schedule, only: [:create, :update, :destroy]
       get 'commercials/render_commercial' => 'commercials#render_commercial'
       resources :commercials, only: [:index, :create, :update, :destroy]