Support Elasticache

[dylanratcliffe]

Elasticache is AWS's managed Redis. This would be pretty cool to be able to support since we would get visibility basically "inside" the application. We would also need to think hard about how linking would work. We would want applications that use this Redis service to be linked to it in the blast radius, so would need to look at how to configure an app to use Elasticache and how we can find these links