Summary:
This speeds up TLS handshake and might be a factor of liger perf regression.
The enabling is guarded by an #ifdef. The condition itself is defined in an
openssl patch.

Test Plan: folly unit tests pass. Tried on devices as well and from tcpdump data was sent before the new ticket was received, essentially speeded up the handshake process.

Reviewed By: subodh@fb.com

Subscribers: trunkagent, kmdent, seanc, benyluo, ssl-diffs@, ranjeeth, folly-diffs@

FB internal diff: D1806856

Tasks: 5284979

Signature: t1:1806856:1422494521:0a048ea9001da13b5d698b5a764d1e66dcbedc99