Function for auth_token middleware config

Each project was configuring the auth_token middleware using several
lines of inisets. Since all the projects should configure the
auth_token middleware in the same way create a function and call it.

Change-Id: I3b6727d5a3bdc0ca600d8faa23bc6db32bb32260
diff --git a/lib/zaqar b/lib/zaqar
index 43fb5a1..19dc509 100644
--- a/lib/zaqar
+++ b/lib/zaqar
@@ -107,11 +107,7 @@
     iniset $ZAQAR_CONF DEFAULT log_file $ZAQAR_API_LOG_FILE
     iniset $ZAQAR_CONF 'drivers:transport:wsgi' bind $ZAQAR_SERVICE_HOST
 
-    iniset $ZAQAR_CONF keystone_authtoken auth_protocol http
-    iniset $ZAQAR_CONF keystone_authtoken admin_user zaqar
-    iniset $ZAQAR_CONF keystone_authtoken admin_password $SERVICE_PASSWORD
-    iniset $ZAQAR_CONF keystone_authtoken admin_tenant_name $SERVICE_TENANT_NAME
-    iniset $ZAQAR_CONF keystone_authtoken signing_dir $ZAQAR_AUTH_CACHE_DIR
+    configure_auth_token_middleware $ZAQAR_CONF zaqar $ZAQAR_AUTH_CACHE_DIR
 
     if [ "$ZAQAR_BACKEND" = 'mysql' ] || [ "$ZAQAR_BACKEND" = 'postgresql' ] ; then
         iniset $ZAQAR_CONF drivers storage sqlalchemy