Update default SSL cipher list to be more secure

Currently: "ALL:!aNULL:!ADH:!eNULL:!LOW:!EXP:RC4+RSA:+HIGH:+MEDIUM" Proposed: "ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES: DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS"

This was taken from: https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/#fnref2 (scroll up 2 lines)

I've tested this successfully against https://www.ssllabs.com/ssltest/ in combination with the patch for #2071 (closed). The only OS/Browser combination failing is: IE 6 / XP