Remove explicit listing of TLSv1 / SSLv3

The explicit protocol list meant this config previously excluded TLS 1.1 and 1.2.

"Since versions 1.1.13 and 1.0.12, nginx uses “ssl_protocols SSLv3 TLSv1 TLSv1.1 TLSv1.2” by default." - http://nginx.org/en/docs/http/configuring_https_servers.html

Add -SSLv2 to the cipher list for safety in case this config is used with an old (<0.8.18) version of nginx.