Cannot found MongoNotebookRepo in 0.9.0-SNAPSHOT

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Hi everyone, we use MongoNotebookRepo in 0.8.0 in the past, but I found that in 
latest 0.9.0-SNAPSHOT the MongoNotebookRepo doesn't appear in zeppelin-plugins 
module, so I want to know if there any plan to restore  the MongoNotebookRepo?