Feature request: Ignore sockets (and maybe other special file types?)

[NiceGuyIT]

Using ouch to compress a directory fails if the directory has a socket. The archive is not created.

$ ouch compress --format tar.zst application backup.tar.zstd
[ERROR] failed to open file `application/daphne.sock`

tar skips the file allowing the archive to be created.

$ tar --use-compress-program zstd --create --file backup.tar.zstd application
/usr/bin/tar: application/daphne.sock: socket ignored

It may make sense to ignore other special files as well.