Catalog Feature: Date last updated for every store

[jbusecke]

Not urgent, just collecting this here. It would be nice to display the date a store was last updated. I have my template set up to write the git hash and time of recipe execution into the store itself. I wonder if this could be parsed during the catalog creation.
cc @andersy005

[norlandrhagen]

I like this organizational structure @jbusecke