Isolate guest DNS from host network
Isolate guest DNS from host network

Use VirtualBox's DNS proxy feature so that the VM never refers to the host's
NSs from DHCP. This prevents hangs when working outside the office.

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet