Previously we would detect the system openssl on OSX, and then fail
to use it, since we required Open 1.0.1 or later.  That's silly!

Instead of looking for RAND_add(), look for TLSv1_1_method(): it was
introduced in 1.0.1, and is also present in LibreSSL.

Also, add the hombebrew path to our search path here.

Fixes bug 23602; bugfix on 0.2.7.2-alpha.