Add server persistence for operation policy names

This change updates the KMIP engine to process and persist the
value of the operation policy name attribute when creating or
registering new managed objects. Tests are included for these
changes.

kmip/services/server/engine.py

@@ -603,6 +603,8 @@ class KmipEngine(object):
                 for e in enums.CryptographicUsageMask:
                     if e.value & attribute_value.value:
                         value.append(e)
+            elif attribute_name == 'Operation Policy Name':
+                field = 'operation_policy_name'
 
             if field:
                 existing_value = getattr(managed_object, field)