updated deprecated method #parent_prefixes

DEPRECATION WARNING: Overriding `ActionController::Base::parent_prefixes` is deprecated, override `.local_prefixes` instead.

9) Perth::LanguagesController GET renders list as HTML
     Failure/Error: check_uri("/perth/#{table_name}.#{format}", format, template)
     NoMethodError:
       super: no superclass method `parent_prefixes' for Perth::LanguagesController:Class
     # /home/korobkov/.bundler/ruby/2.1.0/gems/active_scaffold-3.4.12/lib/active_scaffold/core.rb:125:in `parent_prefixes'
     # /home/korobkov/.bundler/ruby/2.1.0/gems/actionview-4.2.0/lib/action_view/view_paths.rb:46:in `handle_deprecated_parent_prefixes'