Support address mapping for nodes

[kevinbosak]

Description

Currently when connecting to a cluster, the node addresses are given initially. But when a call to Refresh is made, the nodes may report a different IP than those initially used. This can happen, for example, when running the cluster inside of docker and trying to connect from outside of docker. To account for this, a node address mapping could be given, so that redisc will map the addresses reported by the nodes to different addresses. This is currently done in a node redis module: node-redis.

Use case

When developing locally, it can be useful to have a cluster running using docker, but running tests from the host machine. This is currently an issue I am experiencing due to how our integration tests are run.