PATCH is the correct HTML verb to map to the #update action. The
semantics for PATCH allows for partial updates, whereas PUT requires a
complete replacement.

Changes:
* adds config.default_method_for_update you can set to :patch
* optionally use PATCH instead of PUT in resource routes and forms
* adds the #patch verb to routes to detect PATCH requests
* adds #patch? to Request
* changes documentation and comments to indicate support for PATCH

This change maintains complete backwards compatibility by keeping :put
as the default for config.default_method_for_update.

If passed "foo", a gem "foo-rails" is added to the Gemfile
and "foo" and "foo_ujs" are required in the application
JavaScript manifest.

changed asset_timestamps_cache to asset_ids_cache, added an rdoc comment to the new public api, and updated the railtie

corrected the AV railtie to use the new home for cache_asset_timestamps, and merged asset id caching and asset paths together.

Move Rails::LogSubscriber to ActiveSupport::LogSubscriber, allowing frameworks like ActiveRecord and ActiveResource to log outsude Rails::Application [#4816 state:resolved]

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

should run during framework load do:

ActiveSupport.on_load(:action_controller) do
  # Code run in the context of AC::Base
end

Move application configuration to the application configuration object, remove railtie_name and engine_name and allow to set the configuration object.

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

	* Rename <framework>/rails.rb -> <framework>/railtie.rb
	* Rails::Plugin -> Rails::Railtie
	* Rails::Plugin::Vendored -> Rails::Plugin