Update keystone default softparams

Moves _param:keystone_tokens_expiration: 3600 definition
into defaults/openstack/init.yml

Add default soft params for the keystone fernet rotation:
keystone_fernet_rotate_rsync_minute = 0
keystone_fernet_rotate_rsync_hour = '*'

Add default soft param for the keystone [token] allow_expired_window:
keystone_tokens_allow_expired_window = ''

Adjuststed the max_active_keys default value according to the following defaults:
``[token] allow_expired_window`` = 172800 (48 hours)
``[token] expiration`` = 3600 (1 hour)
  rotation_frequency = 1 hour (keystone_fernet_rotate_rsync_minute/hour = 0 *)

max_active_keys = (allow_expired_window + expiration)/rotation_frequency + 2
keystone_tokens_max_active_keys = 51

Change-Id: I7a2a252afb34de9f3c7c4a1549f67d534959ecf9
Related-Prod: PROD-27591
diff --git a/keystone/server/fernet_rotation/cluster.yml b/keystone/server/fernet_rotation/cluster.yml
index c34c4f8..cf7b328 100644
--- a/keystone/server/fernet_rotation/cluster.yml
+++ b/keystone/server/fernet_rotation/cluster.yml
@@ -36,7 +36,8 @@
           command: '/var/lib/keystone/keystone_keys_rotate.sh -r -s -t fernet >> /var/log/keystone/keystone-rotate.log 2>> /var/log/keystone/keystone-rotate.log'
           enabled: true
           user: keystone
-          minute: 0
+          minute: ${_param:keystone_fernet_rotate_rsync_minute}
+          hour: ${_param:keystone_fernet_rotate_rsync_hour}
         keystone_credential_rotate_rsync:
           command: '/var/lib/keystone/keystone_keys_rotate.sh -r -s -t credential >> /var/log/keystone/keystone-rotate.log 2>> /var/log/keystone/keystone-rotate.log'
           enabled: true