Move rigboard templates up a level

Also:
- Find and replace panel -> card
- Some base template work
- gulpfile things, added dep on django-gulp

RIGS/templates/eventauthorisation_client_success.txt

@@ -0,0 +1,11 @@
+Hi {{ to_name|default_if_none:"there" }},
+
+Your event N{{object.event.pk|stringformat:"05d"}} has been successfully authorised for £{{object.amount}} by {{object.name}} as of {{object.event.last_edited_at}}.
+
+{% if object.event.organisation and object.event.organisation.union_account %}{# internal #}
+Your event is now fully booked and payment will be processed by the finance department automatically.
+{% else %}{# external #}
+Your event is now fully booked and our finance department will be contact to arrange payment.
+{% endif %}
+
+TEC PA & Lighting