This commit also cleans up the rake tasks that were checking for DATABASE_URL in different places. In fact, it would be nice to deprecate DATABASE_URL usage in the long term, considering the direction we are moving of allowing those in .yml files.
Since plugins were removed, we can clean up a few methods in engines. We also use this opportunity to move `load_console`, `load_tasks` and `load_runner` to Rails::Engine. This means that, if someone wants to improve script/rails for engines to support console or runner commands, part of the work is already done.
…ternal railties rake tasks description.
Your application should *always* reference your application const (as Blog::Application) and Rails.application should be used just internally.