update ssh client config recommendations

Author: elnappo

README.md

@@ -14,9 +14,11 @@ Set up a secure config for OpenSSH Server >= 6.5. This playbook extends your ssh
 #### Recommended `~/.ssh/config`, `/etc/ssh/ssh_config`
 ``` 
 Host *
+    HashKnownHosts yes
 	PasswordAuthentication no
 	PubkeyAuthentication yes
 	ChallengeResponseAuthentication no
+    HostKeyAlgorithms [email protected],[email protected],ssh-ed25519,ssh-rsa,[email protected],[email protected],[email protected],ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256
 	KexAlgorithms [email protected],diffie-hellman-group-exchange-sha256
 	Ciphers [email protected],[email protected],[email protected],aes256-ctr,aes192-ctr,aes128-ctr
 	MACs [email protected],[email protected],[email protected],[email protected],hmac-sha2-512,hmac-sha2-256,hmac-ripemd160,[email protected]
@@ -26,6 +28,7 @@ alias for legacy connections: `alias ssh_ignore="ssh -F /dev/null"`
 
 ## Inspired by
 * [Secure Secure Shell](https://stribika.github.io/2015/01/04/secure-secure-shell.html)
+* [Mozilla Wiki - Security/Guidelines/OpenSSH](https://wiki.mozilla.org/Security/Guidelines/OpenSSH)
 * [BetterCrypto](https://github.com/BetterCrypto/Applied-Crypto-Hardening)
 * [Manpage sshd_config](http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/sshd_config.5)