[RFE] Use libvirt API in test drivers for virtual hardware

[Pavlo Shchelokovskyy]

Libvirt API provides unified interface for connection to different hypervisors via different transports.
Currently the following hypervisors are supported: LXC, OpenVZ, QEMU, VirtualBox, VMware ESX ,VMware Workstation/Player, Xen, Microsoft Hyper-V, IBM PowerVM (phyp), Virtuozzo, Bhyve - The BSD Hypervisor, Paralels.
Full list can be found at: https://libvirt.org/drivers.html.
Also libvirt-python library supports different type of transports like tls, tcp, unix, ssh.
Current development drivers *_ssh are slow because of bash commands usage. They always use ssh connection, while in most cases it doesn't allow to create ironic VM on hardware server due to security reasons.

[Vladyslav Drok (vdrok)]

Copy of whiteboard:

Gerrit topic: https://review.openstack.org/#q,topic:bp/ironic-libvirt-api,n,z

Addressed by: https://review.openstack.org/253096
    Introduce libvirt dirver

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.openstack.org/265189

[Jim Rollenhagen (jim-rollenhagen)]

This is being taken over by the virtualbmc work, right? Can we close it out if so?

[OpenStack Infra (hudson-openstack)]

Change abandoned by Vasyl Saienko (<email address hidden>) on branch: master
Review: https://review.openstack.org/265189

[OpenStack Infra (hudson-openstack)]

Change abandoned by Vasyl Saienko (<email address hidden>) on branch: master
Review: https://review.openstack.org/253096

[Pavlo Shchelokovskyy (pshchelo)]

Moved to Opinion, as the current plan is to utilize virtualbmc for all tests

[OpenStack Infra (hudson-openstack)]

Change abandoned by Pavlo Shchelokovskyy (<email address hidden>) on branch: master
Review: https://review.openstack.org/254421
Reason: virtualbmc seems have reached proper stability, so I am abandoning this spec as it was planned as alternative to *_ssh driver for "virtual" hardware

Nevertheless, if anybody finds it useful, this driver is available as part of ironic-staging-drivers since 0.2.0 release - code [0], docs [1]

[0] http://git.openstack.org/cgit/openstack/ironic-staging-drivers/tree/ironic_staging_drivers/libvirt

[1] http://ironic-staging-drivers.readthedocs.io/en/latest/drivers/libvirt.html