Add a location.height attribute

This permits user to specify height for either unsupported systems
or to speed up the rackview drawing.

confluent_server/confluent/config/attributes.py

@@ -1,7 +1,7 @@
 # vim: tabstop=4 shiftwidth=4 softtabstop=4
 
 # Copyright 2014 IBM Corporation
-# Copyright 2015 Lenovo
+# Copyright 2015-2019 Lenovo
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -183,6 +183,9 @@ node = {
                         'freeform text data without concern for issues in how '
                         'the server will process it.',
     },
+    'location.height': {
+        'description': 'Height in RU of the system (defaults to query the systems)',
+    },
     'location.room': {
         'description': 'Room description for the node',
     },