Update SSL_CONF docs.

Fix some typos and update version number first added: it has now been
backported to OpenSSL 1.0.2.
(cherry picked from commit 4365e4aad97fa37e4a97eb2270a64c03e6547014)
Demo code for SSL_CONF API

Two example programs one for command line argument processing and
one for configuration file processing.
(cherry picked from commit 3646578ae7e29230d7b05a5487ad12990b2ae688)