Add nic1, nic2 naming abstraction

Implements a new active NIC abstraction and naming convention
that allows nic1, nic2, etc. to be translated to actual (active)
network device names like em1, em2 (or eth0, eth1).

This includes some logic to map ordered active nics to the
nic1, nic2 naming scheme. Embedded nics are always listed
first (in sort order) followed by any other active Nics
on the system.

With the new code:

 {"type": "interface", "name": "nic1" }

is automatically translated (internally) to:

 {"type": "interface", "name": "em1" }

This works for all top level "interface" devices, vlans, bonds, and
bridges alike. For vlans the 'device' name is translated instead
of the device name per vlan object conventions.