SECURITY: openssl update

OpenSSL in the Toolbox has now been updated to version 0.9.6k, which includes
all known security fixes.

OpenSSL is not found on the general Toolbox download site because of its
cryptographic content. It is available at a separate site which requires
registration and a password, though it is still a free download.
You can find the updated images at:
http://www6.software.ibm.com/dl/aixtbx/aixtbx-p