Affects Version/s: None
Fix Version/s: 0.7.0
ZEPPELIN-1190, user can create and view checkpoints of note.
However, default notebook repo (VFSNotebookRepo) does not implement checkpoint() and user will see "Couldn't checkpoint note revision: possibly storage doesn't support versioning. Please check the logs for more details." message.
How about use notebook repo that support checkpoint() as a default?
So user can use checkpoint feature with zero configuration.
I think we can use GitNotebookRepo as a default one