Gets or sets the current state of the manifest.
程序集： Microsoft.WindowsAzure.MediaServices.Client（在 Microsoft.WindowsAzure.MediaServices.Client.dll 中）
This value can be one of the following:
Inactive = 0: No pending asset creations remain. All have either completed or encountered an error.
Activating = 1: The manifest is not yet ready to receive files uploaded to the Blob container.
Active = 2: There are IngestManifestAssets pending creations and the Blob container is being monitored.