Expose set ssl ciphers

[jensdpersson]

Exposes the set-ciphers functions in HsOpenSSL as a command line flag.

Example usage for the test server
.cabal/bin/snap-test-server --ssl-port 8003 --ssl-address 0.0.0.0 --ssl-cert path/to/cert_and_key.pem --ssl-key cert_and_key.pem --no-ssl-chain-cert --ssl-ciphers 'TLSv1.2'

The string format for the --ssl-ciphers param is described in https://www.openssl.org/docs/man1.0.2/man1/ciphers.html

Also added a build dep to the test server entry in cabal file to make it build.
Also had to change deprecated Socket.bindSocket to just bind to make it build. (There seemed to be a mechanism to handle this using some macro checking network versions but it did not seem to work)

[jensdpersson]

Argh, tests failing. I'll overload the changed function and update the PR as soon as possible.