* Repo collab now supports basic default roles developer/user/guest like
project collab does
* User/Anon collab for repos and projects are now stored as fields instead of
in dedicated tables, there was never a need for dedicated tables but I didn't
see that before
* Repo push op is now part of `ProjectOperation`
* `RepoRole` and related code has been entirely removed, only project roles
remain and they're used for both repos and projects
* This is the first not-totally-trivial DB migration in Vervis, it's automatic
but please be careful and report errors
We have gained:
* Haskell-side validation of schema changes before their execution
* Report of results of migration process
* Handling of old deployments
However:
* The validation code hasn't been tested yet at all
* Most of the migration list hasn't been applied at all yet
* Adding lists of entities from a model file is NOT VALIDATED!!! It's totally
possible to implement, just need to catch all the small details right
Until now the list of DB migration actions was incomplete, containing only
changes made since I added the migration system itself. It now contains the
2016-08-04 model, and then every change made since then.
IMPORTANT: The 2016-08-04 instance doesn't have a schema version entity at all,
so it is assigned version 0, while the actual version of its schema is 1. I'm
going to patch persistent-migration to allow it to be 1, making the migration
path smooth.