Now that we enter the container namespace to fetch IPs for every
container, there is no need to have 'weave ps' do it.
This does mean we lose Weave MAC addresses, but that is a rather
idiosyncratic feature anyway.
Instead of using Docker, because after Weave Net 2.0 there are no proxy nor
plugin containers.
This has the drawback of not detecting the plugin/proxy in systems running
Weave Net < 2.0 , but I think we can live with it.
- Run the Weave integrations regardless of if weave is detected.
- Make everything backoff and not spam the logs.
- Add miekg dns to vendor.
- Have the app periodically register with weaveDNS, and the probe do lookups there.
- Decide what the local networks are at runtime, not once at startup.
- Correctly resolve app ids, fixes#825
