Variant negotiation

remove created state after test execution, not before the next test.
This prevents the leak of the `ex` table outside of a single test.

Allow setting `request.variant` as an array - an order in which they will be
rendered.

For example:

  request.variant = [:tablet, :phone]

  respond_to do |format|
    format.html.none
    format.html.phone # this gets rendered
  end

Cookies serializer improvements

do not crash when `config/secrets.yml` is blank.

Terminate the backend ourselves on PG 9.2+

This should make it harder to accidentally break this test.

Refactored object rendering in RenderingHelper#render into it's own method

automatically call @foo.to_partial_path

Calling `render @foo` allows local variables but not options to be
passed to the partial renderer. The correct way to render an object AND
pass options to the partial renderer is to pass the object in the
`:partial` parameter. However, there were previously no tests for this
behaviour (in `render_helper_test.rb` at least).

Hide bundler output for `rails new` if quiet option is specified.

Update Travis settings for Rubinius

/cc @Brixen

[Testing Guide] Explain usage of assert_redirected_to with named routes and ActiveRecord objects [ci skip]

[Testing Guide] Explain usage of assert_redirected_to with named routes and Active Record objects [ci skip]

THIS IS A HUGE HACK.  Thor does not allow us to define public methods
without turning them in to "thor tasks".  That means we cannot subclass
the `apply` method and make it public, so we have to make the method
private and call `send` on it.

Reason: i18n whitelists now locales without passing through symbols,
see https://github.com/svenfuchs/i18n/blob/master/lib/i18n.rb#L278.
Therefore, this snippet is no longer a good practice.

This reverts commit ec0664a6.

Documentation: Don't symbolize tainted data. [ci skip]

`I18n.locale=` symbolizes its argument, so passing it `params[:locale]`
allows one to DOS your application by visiting `...?locale=` URLS
repeatedly, with unique values, until the never-GCed symbols monopolize
the available memory.

add patch in HTTP Verb Constraints [ci skip]

A pass over the Getting Started guide sections 1, 2, and 3 [ci skip]

Also added a `cookies_serializer.rb` initializer to the app template.

Stringify the incoming as well to handle incoming symbol keys from
marshalled sessions