Add contestant export feature

config/locales/en.yml

@@ -204,6 +204,7 @@ en:
       create: "Create"
       delete: "Delete"
       edit: "Edit"
+      export: Export
       import: CSV Import
       open: Open
       refresh: Refresh

config/locales/fr.yml

@@ -175,6 +175,7 @@ fr:
       create: "Créer"
       delete: "Supprimer"
       edit: "Modifier"
+      export: Exporter
       import: Importer un CSV
       open: Détails
       refresh: Rafraîchir

config/routes.rb

@@ -20,6 +20,7 @@ Rails.application.routes.draw do
     post "import", to: "contestants#upload_csv"
     get "import/:id", to: "contestants#convert_csv"
     post "import/:id", to: "contestants#finalize_import"
+    get "export", to: "contestants#export"
   end
   resources :passwords, param: :token
   resource :session