Fixed endianness in Curve25519 implementation (no consequence on security). Also added new Curve25519 code for 64-bit platforms.
Slight speed improvement for Curve25519 (m15 implementation on Cortex-M0+).
Activated Curve25519 support for ECDHE cipher suites.
New implementation of Curve25519 (using multiplications of words of 15 bits or so, should be much faster on Cortex M0).