Adds calls to persist notebook state to storage when the notebook data changes
Adds calls to persist notebook state to storage when the notebook data changes

yebrahim/datalab,parthea/datalab,parthea/datalab,parthea/datalab,googledatalab/datalab,yebrahim/datalab,craigcitro/datalab,googledatalab/datalab,craigcitro/datalab,craigcitro/datalab,yebrahim/datalab,yebrahim/datalab,parthea/datalab,googledatalab/datalab,googledatalab/datalab,parthea/datalab,craigcitro/datalab,yebrahim/datalab,parthea/datalab,googledatalab/datalab,craigcitro/datalab,googledatalab/datalab