We still have [this](https://github.com/peterbe/socorro/blob/514f01fdc6972428be9c27a1ca8eac68891067bd/socorro/external/postgresql/base.py#L43). When time allows we should attack that. 
I think, in particular, this is something that we can do now that middleware_app.py is the only application that runs the socorro/external/postgresql/* files and middleware_app.py does define and set up the `database_class` option. 

When we stop the madness of directly making a connection, we will also need to change our test classes so that they too can start using ConnectionContext.