InitVtctld initializes all the vtctld functionnality.

NewActionRepository creates and returns a new ActionRepository, with no actions.

RegisterDebugHealthHandler register a debug health http endpoint for a vtcld server.

ActionRepository is a repository of actions that can be performed on a {Keyspace,Shard,Tablet}.

ActionResult contains the result of an action.

Result is what the backendExplorer returns.