rake db:migrate:status

I submitted a patch for "rake db:migrate:status":

José Valim asked me to email this list to get your feedback on it.

It is a rake task to display the current state of migrations by
comparing db/migrate/* with schema_migrations.

The issue is that migrations are run from the command line yet from
the command line there is no way to see their current state. It's a
black box. You have to check the database directly. That's a tedious
extra step.

And when running migrate up/down/redo, you need a migration version.
There's no autocompletion, so that either means carefully typing out
14 numbers or leaving the command line to cut/paste from the
filename. Another tedious step.

This rake task reveals the current state of all migrations and makes
it easy to target those migrations you want to affect. I also believe
that it will make migrations easier for beginners to manage.