* src/common.h (name_more_files): New proto.
(files_from_option): Remove.
* src/names.c (name_more_files): New file.
(names_options): Fix declaration of the
add-file option.
(names_parse_opt): Handle --add-file.
* src/tar.c (struct tar_args): Remove the input_files member.
Change all uses: use name_more_files() instead.
* tests/Makefile.am: Add new test.
* tests/add-file.at: New testcase.
* tests/testsuite.at: Add new test.
