WS-907: Add back the templates for Mark

This is probably incomplete or incorrect, since there are likely Alembic heads that need to be merged here now, but I remembered I needed to spelunk this from my old broken MR before I leave for the week.

The templates are here, along with some name revisions. You can bring this in whenever you want, before the overall story is complete; I would do it once you think you have all the bits in place that the messages will render correctly.