Added ItemSnapshotter.proto
Added item_snapshotter Go interface
Added framework components for item_snapshotter
Updated plugins doc with ItemSnapshotter info
Added SnapshotPhase to item_snapshotter.go
ProgressOutputOutput now includes a phase as well as an error string for problems that occured
Signed-off-by: Dave Smith-Uchida <dsmithuchida@vmware.com>
Refactor plugin management:
- support multiple plugins per executable
- support restarting a plugin process in the event it terminates
- simplify plugin lifecycle management by using separate managers for
each scope (server vs backup vs restore)
Signed-off-by: Andy Goldstein <andy.goldstein@gmail.com>