Allow setting custom cipher strings in the openssl config file.

When the PROFILE=KEYWORD is specified as a cipher string, openssl will
expand the keyword to the defined cipher string in the configuration
file under section "cipher_profiles". That requires the default
(or any other) configuration file to be loaded.

An example entry in the configuration file:
[ cipher_profiles ]
PROFILE1 = ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384
PROFILE2 = HIGH

Also in: http://rt.openssl.org/Ticket/Display.html?id=3299