CryptoAPI ENGINE.

Add appropriate #ifdefs round client cert functions in headers.

the rest of the certificate chain. Currently unused.

to HEAD (and the 0.9.8 branch).  Remove the reminder.

Fix flaw if 'Server Key exchange message' is omitted from a TLS
handshake which could lead to a cilent crash as found using the
Codenomicon TLS test suite (CVE-2008-1672)

Reviewed by: openssl-security@openssl.org

Obtained from: mark@awe.com