Feature request: Create ability for exported pods packages to be versioned more robustly

[regnskygge]

Using the Migrate Packages component to export a pod (or grouping of pods) is great. In the resulting json export there is a "build" value that is assigned the unix time stamp at the moment of export. However, importing this package of one or more pods into another site loses this meta info. If this timestamp (and a comment/desc field, perhaps?) were to be retained then versioning pods across multiple sites would be more elegant.