Change in vdsm[ovirt-4.0]: hooks: Add localdisk hook

[Code Review]

From Dan Kenigsberg :

Dan Kenigsberg has posted comments on this change.

Change subject: hooks: Add localdisk hook
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Patch Set 1:

(1 comment)

https://gerrit.ovirt.org/#/c/71712/1/vdsm_hooks/localdisk/README
File vdsm_hooks/localdisk/README:

Line 50: The VM must be pinned to host. Any migration will cause the VM to try to
Line 51: start with local disks that are not available on the new host.
Line 52: 
Line 53: The operator need to configure the engine UserDefinedVMProperties to support
Line 54: 'localdisk' with value 'lvm'
better be more specific:

engine-config -s UserDefinedVMProperties='localdisk=^(lvm)?$'
Line 55: 
Line 56: TODO: