use ubuntu 13.10, postgres and nginx with https and custom tls settings

configure nginx to use ephemeral diffie hellman for perfect forward
secrecy with custom generated diffie hellman parameters from
`dh-param-4096.pem`. to generate your own diffie hellman parameters, see
end of `firstrun.sh` script.

https uses a 4096 bit rsa key, http is redirected to https.