CCBC-344/CCBC-425: Add SSL support via OpenSSL

This implements the SSL layer as an implementation of lcbio_TABLE. The
table is injected into the socket when the connection is successfuly
established.

Integration with libcouchbase' core itself (i.e. making operations and
configuration operations go through SSL (if requested)) will be done in
a subsequent commit.

Change-Id: I599bb6a883263e1889c2a87ae423684cd209d1e7
Reviewed-on: http://review.couchbase.org/37336
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Brett Lawson <brett19@gmail.com>