Comment 31 for bug 839595

ubiquity has source specifically for managing /etc/networking/interface (d-i/source/netcfg/write_interface.c) so it seems whatever I am doing during the install is the wrong way to do it. Sorry for the red herring in network-manager, it was just a likely guess since that was the only thing I touched on one of the machines after a clean beta 1 install to set up the wifi network.