Fixed selection of ECDHE_RSA suites for pre-1.2 TLS versions.
Activated Curve25519 support for ECDHE cipher suites.
Added API for external hashing of ServerKeyExchange, and signature algorithm identifiers in the 0x080* format (preparatory steps for EdDSA support).
Added support for client certificates (both client-side and server-side, but still missing an API for extracting the client identity from the certificate).