[WIP] [DO NOT MERGE] Router active active

Opening this up for feedback.  This branch contains a working example of round robin wild card DNS via BIND mapping to OpenShift routers.  Definitely needs improvements about how router configs are digested by the DNS container but didn't want to code that up yet if it wasn't on the right track.
I'd say that the proof of concepts here are useful - I just don't see us running this code (yet).  So using this to draft the writeup on how this works, an example zone file, any gotchas or config, is a good place to start.  We might want to create an example bind image at some point in which case we'd use this code to demonstrate the concept (take as ENV vars a list of IP addresses to delegate to), but we probably won't go the full step to DNS yet.

----- Original Message -----
> > @@ -0,0 +1,23 @@
> > +package dns
> 
> There is certainly nothing OpenShift specific about this work.  I just
> followed the router pattern for commands but it definitely doesn't need to
> be part of the OpenShift distro if we don't want it to be.
> 
> RE: running our own DNS server. We don't technically need a server to provide
> out of the box DNS resolution for customers in deployed environments.
> Running DNS as a pod is just an implementation detail, nothing special
> about it.  If we don't intend on doing that then we can disregard this PR.
> 
> RE: customers running their own DNS.  They can do that, they just need to
> know our router IP address that they're assigned to (or, preferably, they
> create a CNAME pointing their custom name to our router name)
> 
> ---
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