Logging in upgrade

[MrLucio]

Make the migrator call the upgrade/downgrade method passing the logger, this way you can use it manually whenever you want.

[rooterkyberian]

can't you have migrations define they own loggers (getLogger("app.migrations.migration_name")) and then configure logger handlers on the application level?

[MrLucio]

I was trying to avoid importing the logging module into every single migration.
If generating migrations would add the logging module (given the proper argument to the method call) that would be a good solution.

[rooterkyberian]

I thought I already implemented custom migration templates, but I guess not (#28).
Adding logger to each migration in default template would be good enough here.