HTools/Types.hs: more auto-repair types

AutoRepairPolicy, AutoRepairStatus, and other auxiliary types are added.
These are used only internally by the auto-repair tool, and parsed from the
various object tags as defined in the design doc.

Signed-off-by: Dato Simó <dato@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>