Renames Legislation model to LegacyLegislation

Renames the model and related stuff from Legislation 
to LegacyLegislation to avoid name clashes with 
the future Legislation module.

config/routes.rb

@@ -79,7 +79,7 @@ Rails.application.routes.draw do
 
   resources :stats, only: [:index]
 
-  resources :legislations, only: [:show]
+  resources :legacy_legislations, only: [:show], path: 'legislations'
 
   resources :annotations do
     get :search, on: :collection