feat(networkd): Adding support for debian-interface-to-networkd conversion

DO NOT MERGE

Adding the initial support for configuring the network based on a Debian interfaces file located on a cloud config drive. This is accomplished by converting the given interfaces file into a series of networkd configs and then reloading networkd.

I suspect that the process by which the configs are loaded is going to need a bit of work, and I _know_ that the file conversion is going to need some work. Be gentle.