Added TTL for memcached items

Fixes: PROD-26960

Change-Id: Ie5ac5a271ededd06c4372b0ee45e23a76f164492
diff --git a/oslo_templates/files/queens/oslo/_cache.conf b/oslo_templates/files/queens/oslo/_cache.conf
index 8a41354..53ec78b 100644
--- a/oslo_templates/files/queens/oslo/_cache.conf
+++ b/oslo_templates/files/queens/oslo/_cache.conf
@@ -13,6 +13,7 @@
 # region. This applies to any cached method that doesn't have an
 # explicit cache expiration time defined for it. (integer value)
 #expiration_time = 600
+expiration_time = {{ _data.get('expiration_time', 600) }}
 
 # Cache backend module. For eventlet-based or environments with
 # hundreds of threaded servers, Memcache with pooling
@@ -41,6 +42,11 @@
 # per argument to be passed to the dogpile.cache backend. Example
 # format: "<argname>:<value>". (multi valued)
 #backend_argument =
+{%- for opt_name,opt in _data.get('backend_argument', {}).iteritems() %}
+{%- if opt.get('enabled', True) %}
+backend_argument = {{ opt.get('name', opt_name) }}:{{ opt.value }}
+{%- endif %}
+{%- endfor %}
 
 # Proxy classes to import that will affect the way the dogpile.cache
 # backend functions. See the dogpile.cache documentation on changing-