Until support for bonding params is added to networkd, this will be neccessary in order to use bonding parameters (i.e. miimon, mode). This also makes it such that the 8012q module will only be loaded if the network config makes use of VLANs.
Currently only supports the ether mode of hwaddress. No immediate plans to support ax25, ARCnet, or netrom.
These tests should be an exhaustive set of tests for the parsing of Debian interface files and generation of equivilent networkd config files.