Add non-recursive process mode for add_files in ArchiveWrite class

[inochisa]

Add non-recursive file process for function add_files with option recursive, also limit add_file only process the entry itself.

Example mtree output for non-recursive mode

#mtree
/set type=file uid=0 gid=0 mode=644
./__init__.py time=1644734613.0 size=601
./entry.py time=1644734613.0 size=12807
./exception.py time=1644734613.0 size=370
./extract.py time=1644734613.0 size=2694
./ffi.py time=1644734613.0 size=12247
./flags.py time=1644734613.0 size=211
./read.py time=1644734613.0 size=5514
./write.py time=1644734613.0 size=10227
./__pycache__ time=1644734613.0 mode=755 type=dir