Make the Rack::SSL middleware configurable

If you are coming from a Rails 3.0 application, you won't have
the correct Bundler require statement.

This will cause the gems under the `assets` group not to be available
in the development and production environment.

I think this is related to the issue #39 in rails-sass
https://github.com/rails/sass-rails/issues/39

Closes #2807.

Correctly override image_path in sprockets rails_helper

Avoid use of existing precompiled assets during rake assets:precompile run

Fix: habtm doesn't respect select query method

Give precedence to `config.digest = false` over the existence of manifest.yml asset digests

Closes #3104.

Previously, it would use send() to get the attribute. In Active
Resource, this would rely on hitting method missing. If a method with
the same name was defined further up the ancestor chain, that method
would wrongly be called.

This change fixes test_to_xml_with_private_method_name_as_attribute in
activeresource/test/cases/base_test.rb, which was broken after
51bef9d8, because that change made
to_xml use serializable_hash.

CollectionProxy#replace should change the DB records rather than just mutating the array. Fixes #3020.

The options argument to MessageVerifier#initialize should be a hash.