* before_configuration: this hook is run immediately after the Application class
comes into existence, but before the user has added any configuration. This is
the appropriate place to set configuration for your plugin
* before_initialize: This is run after all of the user's configuration has completed,
but before any initializers have begun (in other words, it runs right after
config/environments/{development,production,test}.rb)
* after_initialize: This is run after all of the initializers have run. It is an
appropriate place for forking in a preforking setup
Each of these hooks may be used via ActiveSupport.on_load(name) { }. In all these cases, the context inside the block will be the Application object. This means that for simple cases, you can use these hooks without needing to create a Railtie.
add lazy_load_hooks.rb, which allows us to declare code that
should be run at some later time. For instance, this allows
us to defer requiring ActiveRecord::Base at boot time purely
to apply configuration. Instead, we register a hook that should
apply configuration once ActiveRecord::Base is loaded.
With these changes, brings down total boot time of a
new app to 300ms in production and 400ms in dev.
TODO: rename base_hook
