route namespace

design notes for #850

I estimate completing the implementation will take half a day.


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UPDATE (from Adam): This took over a day to change it from design to implementation, including hours of pairing, but the estimate was for Jean-Paul alone and I'm slower. There are also a few TODOs with questions about how to continue.

Fixes #850 

The `create_proxy_to` and `enumerate_proxies` methods need to know about the namespace they're acting on, so my view is yes, `namespace` should be a third, required parameter of those two methods in the `INetwork` interface. It should definitely not be an attribute of that interface - interfaces shouldn't have attributes at all and `namespace` is probably not very useful as an attribute of anything implementing `INetwork` either, given its only purpose would be to supply a namespace value to an interface that's public anyway.