MAINT: use retrieve only as default argument when calling from the cmd line

src/caoscrawler/crawl.py

@@ -1117,6 +1117,7 @@ def parse_args():
                         help="The subtree of files below the given path will "
                         "be considered. Use '/' for everything.")
     parser.add_argument("-s", "--security-mode", choices=["retrieve", "insert", "update"],
+                        default="retrieve",
                         help="Determines whether entities may only be read from the server, or "
                         "whether inserts or even updates may be done.")
     parser.add_argument("-n", "--dry-run", action="store_true",