Prevent unexpected erasing nodes during image based provision
Prevent unexpected erasing nodes during image based provision

Classic provisioning flow:

bootstrap -> erase -> reboot -> provisioning (node do not respond via mcollective) -> reboot -> target

If system is backed online via mcollective and return bootstrap status, it will be erased.

Image flow before this change:

bootstrap -> erase -> provisioning (node still can respond via mcollective) -> reboot -> target

Sometimes we can ask nodes about status in case of image flow
before they will be rebooted. And send them to erase if they are answered 'bootstrap'. To prevent such situation, we add
new systemtype 'image'.

Now workflow will be looked:

bootstrap -> erase -> image -> provisioning (node still can respond via mcollective) -> reboot -> target

We marked nodes with 'image' systemtype as not provisioned, but do not try to erase them.

This new type should not block any other operations with node:

* delete;
* stop provisioning;
* reprovisioning.

Change-Id: I7fcc32c604526575d7805386ecfe3d0d40cbd12e
Closes-Bug: #1427718

stackforge/fuel-astute,eayunstack/fuel-astute,stackforge/fuel-astute,eayunstack/fuel-astute