Fixing error when connecting to Redis with a password

Fixes balderdashy/sails-redis/issues/42

Due to `client.auth()` not returning a client instance, the call to `client.once()` was blowing up.  This PR fixes that.

PS: The tests still fail due to balderdashy/sails-redis/issues/40 .  Cardinal sin to submit a PR with broken tests I know.  But it's for the safety of humanity ;)