merb-plugins

It would be nice if one were able to configure merb_datamapper to specify a custom database configuration file from the init.rb file like so:

Merb::BootLoader.before_app_loads do
  Merb::Plugins.config[:datamapper] = {
    :config_file => Merb.root / "config" / "database.alt.yml"
  }
end

It's not as simple as overwriting Merb::Orms::Datamapper.config_file() because the database is connected to immediately after the gem is loaded, which gives no time to overwrite the module.

The attached patch adds the ability to specify a custom config database file.