Support --bip and --mtu on Ubuntu
Support --bip and --mtu on Ubuntu

This wasn't included in https://github.com/garethr/garethr-docker/commit/9e0ffcc12982dfef23724c196e70965e25a1962d
snahelou/garethr-docker,nickchappell/garethr-docker,benlangfeld/garethr-docker,bmcbm/garethr-docker,twc-openstack/garethr-docker,HackerHappyHour/hackerhappyhour-docker,bmcbm/garethr-docker,twc-openstack/garethr-docker,wscheele/garethr-docker,HackerHappyHour/hackerhappyhour-docker,rchicoli/puppet-docker,rchicoli/garethr-docker,Tradeshift/garethr-docker,Tradeshift/garethr-docker,SUNET/garethr-docker,bmcbm/garethr-docker,HackerHappyHour/hackerhappyhour-docker,wscheele/garethr-docker,garethr/garethr-docker,twc-openstack/garethr-docker,rchicoli/puppet-docker,benlangfeld/garethr-docker,benlangfeld/garethr-docker,rchicoli/garethr-docker,SUNET/garethr-docker,rchicoli/garethr-docker,nickchappell/garethr-docker,snahelou/garethr-docker,wscheele/garethr-docker,rchicoli/puppet-docker,garethr/garethr-docker,snahelou/garethr-docker,garethr/garethr-docker,SUNET/garethr-docker,Tradeshift/garethr-docker,nickchappell/garethr-docker