This reverts commit 83cb6fbd.

Reason: very trivial

[ci skip]

* Fix example queries
* Remove doc entries of where.like/not_like.
* Remove :chain from where.not related docs. To me that's an implementation
  detail and we don't expect people to use where(:chain).not.

Fix #assert_instance_method to also assert indented methods

use _action callbacks in actionmailer

Use attr_accessor for Rails.{application,cache,logger}

Update AR Changelog with correct example using includes [ci skip]

These queries don't seem to work without the includes clause. [ci skip]

Update guides to use _action callbacks [ci skip]

use :only instead of :except callback option in the controller template

Mailers are always async now, and we already discuss
queueing lower down in the guide.

There's no reason for guides to reference old behaviors. They should
be current as of the versions of Rails that they ship with, and including
older information just clutters thing.

I discussed this change with @fxn and he agrees.

Fix a typo in rdoc (*expect* for *except*)

As [Security Guide](http://edgeguides.rubyonrails.org/security.html#whitelists-versus-blacklists)
says, it's better to use `before_filter only: []` instead of `except: []`
so we don't forget to turn the filter off for newly added actions.

Actionize2

Actionize: Use `_action` callbacks in documentation and code

Rename ActiveSupport::BasicObject to ActiveSupport::ProxyObject

AS::BasicObject is used for proxy classes. Let's give it a less concerning
name. Also, it avoids the confusion with Ruby's Basic Object.

The real win with these chain methods is where.not, that takes care of
different scenarios in a graceful way, for instance when the given value
is nil.

    where("author.id != ?", author_to_ignore.id)
    where.not("author.id", author_to_ignore.id)

Both where.like and where.not_like compared to the SQL versions doesn't
seem to give us that much:

    Post.where("title LIKE 'ruby on%'")
    Post.where.like(title: 'ruby on%'")
    Post.where("title NOT LIKE 'ruby on%'")
    Post.where.not_like(title: 'ruby on%'")

Thus Rails is adding where.not, but not where.like/not_like and others.

Document the types of arguments accepted by AR#not

This commit stems from https://github.com/rails/rails/pull/8332#issuecomment-11127957

Since the formats in which conditions can be passed to `not` differ
from the formats in which conditions can be passed to `like` and `not_like`,
then I think it's worth adding rdoc and tests to show this behavior