Add ssl support on redis queue

[omerra]

Kombu doesn't support redis with SSL connection, this used to make sense because redis on python didn't support this.
However new version of redis-py (2.10+) support easy ssl connection: Redis(ssl=False, ssl_keyfile=None, ssl_certfile=None, ssl_cert_reqs=None, ssl_ca_certs=None, **kwargs)
And there is a new connection class for redis: SSLConnection.
With the way kombu is currently setup, it is possible to search for these ssl params in the options passed, and use SSLConnection instead of normal Connection class

[ghost]

@ask Do you happen to know if this feature exists in Kombu? Are there plans to implement it?

If there's no action planned, we can probably close this issue.

[ask]

@MrTomWhite Pretty simple to implement, as we already support Connection(ssl=dict) :)