Feature-parity with SSH commands via symlinks

[sr229]

I think TinySSHD would have a lot of reception if we can have feature parity command-wise with OpenSSH/Dropbear.

commands like ssh, ssh-keygen, sshd, etc. can be symlinked and recognized in the tinyssh-specific command. Just a little thought since you can't really drop-in replace using TinySSH since it'll break with applications like Ansible.