Add simple service redirection

This adds a simple redirection handler, so that you can call ```GET /api/v1beta1/redirect/services/myService``` and get back a 307 and a Location header set with an IP:port that will let you talk to myService. This is a very rudimentary form of discovery that is inferior to our final solution in every way except for existing.

@smarterclayton This is a simple idea about how to send requests to a service running in a k8s cluster from outside of that cluster, inspired by the conversation about having a build system. This would NOT be the way I expect to talk to actual k8s plugins.
Does remoteLocation need to be typed to a URL, or an opaque value?  The implication of 307 is http transformation, but I'm wondering whether in many cases I may want to be redirected to something like a dns name, a tcp endpoint, a tcp endpoint with a port, or even possibly a key in a global store (to stretch the case as much as possible).  In introducing this, do we want to limit it to only things that can be URLs, only things that can be HTTP (which for services, we really have no idea whether they're http), or simply an opaque value that clients are required to understand?