Updates the spec and plugins to return an array of interfaces and IP details
to the runtime including:
- interface names and MAC addresses configured by the plugin
- whether the interfaces are sandboxed (container/VM) or host (bridge, veth, etc)
- multiple IP addresses configured by IPAM and which interface they
have been assigned to
Returning interface details is useful for runtimes, as well as allowing
more flexible chaining of CNI plugins themselves. For example, some
meta plugins may need to know the host-side interface to be able to
apply firewall or traffic shaping rules to the container.
Using a new ".configlist" file format that allows specifying
a list of CNI network configurations to run, add new libcni
helper functions to call each plugin in the list, injecting
the overall name, CNI version, and previous plugin's Result
structure into the configuration of the next plugin.
