Initial implementation of Data.update_from_data.
Initial implementation of Data.update_from_data.

This takes another dataset and matches components based on labels. Components no longer in the new dataset are removed, components in both datasets have their numerical values updated, and components only in the new data are added.
saimn/glue,saimn/glue,stscieisenhamer/glue,stscieisenhamer/glue