Added django-maintenancemode middleware.

doc/README

@@ -42,6 +42,7 @@ We need glue.ligolw, which requires SOOO many things from pylal
     pip install django
     pip install pytz
     pip install simplejson
+    pip install django-maintenancemode
 
 nfs0001
     certs

settings/default.py

@@ -3,6 +3,7 @@
 
 DEBUG = False
 TEMPLATE_DEBUG = DEBUG
+MAINTENANCE_MODE= False
 
 EMAIL_HOST = 'gravity.phys.uwm.edu'
 
@@ -194,6 +195,7 @@ MIDDLEWARE_CLASSES = [
 #   'ligodjangoauth.LigoShibbolethMiddleware',
     'ligoauth.middleware.auth.LigoAuthMiddleware',
 #   'django.contrib.auth.middleware.RemoteUserMiddleware',
+    'maintenancemode.middleware.MaintenanceModeMiddleware',
 ]
 
 ROOT_URLCONF = 'urls'

templates/503.html

+{% extends "base.html" %}
+
+{% block title %}503 – Service Unavailable{{ object.graceid }}{% endblock %}
+{% block heading %}Not Found {{ object.graceid }}{% endblock %}
+
+{% block content %}
+    <p>GraceDb is temporarily unavailable.  Please check back later.</p>
+    {{ message|safe }}
+{% endblock %}