Utilities: Add the `-c` option to `install`

Userland/Utilities/install.cpp

@@ -19,6 +19,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     StringView destination;
 
     Core::ArgsParser args_parser;
+    args_parser.add_ignored(nullptr, 'c'); // "copy files" is the default, no contradicting options exist.
     args_parser.add_option(create_leading_dest_components, "Create leading components of the destination path", nullptr, 'D');
     args_parser.add_positional_argument(source, "Source path", "source");
     args_parser.add_positional_argument(destination, "Destination path", "destination");