Enable ECDH cipher support
With OpenSSL 1.0.0, default key parameter is NIST P-384 rather than NIST P-256
(default for Apache) to ensure RFC 6460 compliance for AES-256 encryption.
With OpenSSL 1.0.2, the key parameter is automatically chosen.
Merge pull request #987 from alanswanson/master

Enable ECDH cipher support. Thanks @alanswanson for this patch and fixing #984 !!