(Called "cut through" for historical reasons in this patch.)

Enables SSL3+ clients to send application data immediately following the
Finished message even when negotiating full-handshakes.  With this
patch, clients can negotiate SSL connections in 1-RTT even when
performing full-handshakes.

Initial fork from f2d678e6e8 (1.0.2 beta).

(This change contains substantial changes from the original and
effectively starts a new history.)