Enh: Order packages by oldest to newest??

[lwasser]

This is a double edged sword but the diff on packages.yml and contribs. yml in the pyopensci.github.io repo are difficult to parse because if new packages end up at the top - then the file has changed all the way down making it difficult to see what really has changed in the update.

For packages the fix is easy - sort by date-accepted which will never change. i think we could likely create a serialization output step to implement this easily.

For new people it's a bit trickier. Perhaps when add_new is run, we can add a boolean flag (new=True) and sort that way? this one needs to be thought through a bit more. it's hard to really understand when a user was added as the all-contribs bot doesn't add a date .