Update ssl ciphers

Removing all DHE suites from Nginx template SSL ciphers.

This will deny forward secrecy for Android 2.3.7, Java 6 and OpenSSL 0.9.8. but will give A+ rating on SSL labs.

Google sites also do not have DHE suites, [source](https://community.qualys.com/blogs/securitylabs/2013/06/25/ssl-labs-deploying-forward-secrecy)

> Google's sites, for example, tend to not have any DHE suites in their configuration. [2013]

See merge request !814