settings: add environment variable for setting the cache backend

compte_agglo_montpellier/settings.py

@@ -197,6 +197,13 @@ if 'INTERNAL_IPS' in os.environ:
 else:
     INTERNAL_IPS = ('127.0.0.1',)
 
+# cache
+CACHES = {
+    'default': {
+        'BACKEND': os.environ.get('CACHE_BACKEND', 'django.core.cache.backends.locmem.LocMemCache'),
+    },
+}
+
 # misc
 SECRET_KEY = os.environ.get('SECRET_KEY', '0!=(1kc6kri-ui+tmj@mr+*0bvj!(p*r0duu2n=)7@!p=pvf9n')
 DEBUG_TOOLBAR_CONFIG = {'INTERCEPT_REDIRECTS': False}