Depending on load order of libraries as well as version of ruby, need to
require open3 before attempting to reference `Open3`.
There is an additional dependency on qemu-utils to dynamically retrieve
the image information to provide the virtual size and format
automatically. Add this to the docker image to ensure it's available for
users of this distribution format.
Fixes: #1305
To be able to use 'vagrant ssh' from within the docker container, it is
necessary to run within the host network context.
Include a helper alias suggestion and a note about a current issue in
passing arguments to vagrant options which impacts the 'vagrant ssh -c
...' syntax with an alternative.
Provide a docker image that supports execution of vagrant-libvirt
provided the host system has docker and libvirt installed. This can help
side step many of the library compatibility issues experienced by users
by providing an alternative way to run the latest code should their
distribution not have a natively packaged vagrant.
