adding extra documentation

ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py

@@ -73,7 +73,7 @@ def main():
     parser.add_argument("-t", "--token", default="ad9b37a24380948601257f9c1f889b07a00ac81e",
                         help="Token to access the REST API of ldvspec", action="store")
     parser.add_argument("--host", nargs="?", default='dev',
-                        help="The ldv-spec-db host. Presets are 'dev', 'test', 'prod', otherwise give a full url like https://sdc.astron.nl:5554/ldvspec/api/v1")
+                        help="The ldv-spec-db host. Presets are 'dev' (default), 'test', 'prod', otherwise give a full url like https://sdc.astron.nl:5554/ldvspec/api/v1")
     parser.add_argument("--configuration", default='~/shared/ldv_migrate.cfg',
                         help="Configuration file containing tunnel and ldvadmin database credentials")
     parser.add_argument("-s", "--section", default='postgresql-ldv',