FEATURE: Include more enums (PR #78)

This adds several new enums to help Data Explorer users quickly reference the meaning of the more obscure column values. It also moves reviewables.status to the main enum list since the reviewables table has been established for quite some time now. We could probably remove queued_posts.state as well, but it does act as an example of how to handle tables that aren’t fully established or those that have been recently removed.


Nice change!