webchat example: use file on disk rather than in-memory database. not sure...

webchat example: use file on disk rather than in-memory database. not sure why, but :memory: now gives me OperationalError: no such table django_session

examples/webchat/settings.py

@@ -6,7 +6,7 @@ TEMPLATE_DEBUG = DEBUG
 ADMINS = ()
 MANAGERS = ADMINS
 DATABASE_ENGINE = 'sqlite3'
-DATABASE_NAME = ':memory:'
+DATABASE_NAME = '/tmp/gevent-webchat.sqlite'
 DATABASE_USER = ''
 DATABASE_PASSWORD = ''
 DATABASE_HOST = ''