Add support for network adapter hotplug.

    This patch makes it possible to add/del instance
    interface other than booting time.
    Implement bp:network-adapter-hotplug

Originally from change Ibee003a9ec6cc9b3fd275417caccd0c67f6c871f

Co-authored-by: Yaguang Tang <heut2008@gmail.com>
Co-authored-by: Édouard Thuleau <edouard.thuleau@orange.com>

Change-Id: I4f8f677af58afcb928379e5cf859388d1da45d51
PowerVMDiskAdapter detach/cleanup refactoring

Define PowerVMDiskAdapter interface as contract for implementation

Change order lpar, disk devices and volumes are cleaned up

Change-Id: I0004b0d71cb8a8dd9c4d502dd1278c10bdc7c8e2
Merge "PowerVMDiskAdapter detach/cleanup refactoring"
Merge "Add support for network adapter hotplug."