build,src: remove sslv3 support

SSLv3 is susceptible to downgrade attacks.  Provide secure defaults,
disable v3 protocol support entirely.

PR-URL: https://github.com/iojs/io.js/pull/315


Reviewed-By: Fedor Indutny <fedor@indutny.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>