* Users should not be able to manipulate the name or order of migrations, after loading them.
… to nil, to reduce Object creation.
… Property constant missing bug on Ruby 1.9.1.
…n' actions of the migration.
* Other libraries might want to use different messages.
* The previous approach relied on the adapters being setup, which may not always be true if bundler is being used. Sure, we could tell people to use :require => nil on adapters, but I would rather not have to explain that exception every-time this or related problems appear. * Even though this was not strictly related to #1280, I am tagging it with the bug because it is the exact same problem as with transactions [#1280]