Update docs and template to use 2 Redis databases

Switch default installation to use two Redis databases. One for
the message broker, and the other to store task results.

Signed-off-by: Roberto Rosario <roberto.rosario@mayan-edms.com>

HISTORY.rst

@@ -176,6 +176,9 @@
   to John Bentley (@johnbentleyii) for the report.
 - Add missing Event class cache invalidation when
   calling the refresh() method.
+- Switch default installation to use two Redis
+  databases. One for the message broker, and the
+  other to store task results.
 
 3.2.9 (2019-11-03)
 ==================

docs/chapters/deploying.rst

@@ -160,7 +160,7 @@ For another setup that offers more performance and scalability refer to the
 
         sudo echo "maxmemory-policy allkeys-lru" >> /etc/redis/redis.conf
         sudo echo "save \"\"" >> /etc/redis/redis.conf
-        sudo echo "databases 1" >> /etc/redis/redis.conf
+        sudo echo "databases 2" >> /etc/redis/redis.conf
         sudo systemctl restart redis
 
 13. Enable and restart the services [1_]:

mayan/apps/platform/classes.py

@@ -155,7 +155,7 @@ class PlatformTemplateSupervisord(PlatformTemplate):
         ),
         YAMLVariable(
             name='CELERY_RESULT_BACKEND',
-            default='redis://127.0.0.1:6379/0',
+            default='redis://127.0.0.1:6379/1',
             environment_name='MAYAN_CELERY_RESULT_BACKEND'
         ),
         YAMLVariable(