wip extranet registration

app/controllers/admin/communication/extranets_controller.rb

app/models/communication/extranet.rb

app/models/user/with_extranet.rb

app/views/admin/communication/extranets/_form.html.erb

config/locales/communication/en.yml

config/locales/communication/fr.yml

config/locales/extranet/en.yml

config/locales/extranet/fr.yml

...08_add_registration_contact_to_communication_extranets.rb

db/schema.rb

test/fixtures/communication/extranets.yml

test/models/communication/extranet_test.rb