Libssh: OpenSSL Dep

Libssh taps OpenSSL, but does’t tap the Homebrew version and consequently is pulling in the insecure standard OS X version. This fixes this, and forces a recompile.

```
-- checking for module 'openssl'
--   found openssl, version 0.9.8za
-- Found OpenSSL: /usr/lib/libssl.dylib;/usr/lib/libcrypto.dylib
-- Looking for openssl/aes.h
-- Looking for openssl/aes.h - found
-- Looking for openssl/blowfish.h
-- Looking for openssl/blowfish.h - found
-- Looking for openssl/des.h
-- Looking for openssl/des.h - found
-- Looking for openssl/ecdh.h
-- Looking for openssl/ecdh.h - found
-- Looking for openssl/ec.h
-- Looking for openssl/ec.h - found
-- Looking for openssl/ecdsa.h
-- Looking for openssl/ecdsa.h - found
```