The validation added in 5a3dc809 will
reject values for the `:on` option for after_commit and after_rollback
callbacks that are string values like `"create"`.

However, the error message says ":on conditions for after_commit and
after_rollback callbacks have to be one of create,destroy,update". That
looks like a string value *would* be valid.

This commit changes the error message to say ":on conditions for
after_commit and after_rollback callbacks have to be one of [:create,
:destroy, :update]", making it clearer that symbols are required.

Fix grammar of sentence in Reflection documentation [ci skip]

[ci skip] add `enable_extension` to PostgreSQL hstore example

Mounted Rack apps should have default named routes based on app name

[ci skip] update rails version to 3.2.21

Add Guides note to change cache namespace

This fixes a regression in 4.2.0 from 4.1.8.

https://github.com/rails/rails/pull/17823 fixed a similar regression regarding _explicitly_ named routes for a mounted Rack app, but there was another regression for the default value.

With a route like:

    Rails.application.routes.draw do
      mount Mountable::Web, at: 'some_route'
    end

The "Prefix" column of rake routes gives the following:

- 4.1.8:         mountable_web
- 4.2.0.beta1-4: [nothing]
- 4.2.0.rc1:     [nothing]
- 4.2.0.rc2:     some_route   <- regression

This fixes the default to go back to being based off the name of the class like the docs specify: https://github.com/rails/rails/blob/785d04e3109f69d0b9b9f4732179592f0ef04e52/actionpack/lib/action_dispatch/routing/mapper.rb#L558-L560

Explicitly named routes still work correctly per https://github.com/rails/rails/pull/17823:

    Rails.application.routes.draw do
      mount Mountable::Web, at: 'some_route', as: 'named'
    end

- 4.1.8:         named
- 4.2.0.beta1-4: [nothing]
- 4.2.0.rc1:     [nothing]
- 4.2.0.rc2:     named

If the tests are interupted and the teardown block doesn't run, the
developer needs to delete these manually in order to be able to run the
tests again.

The type registration was simply looking for the OID, and eagerly
fetching/constructing the sub type when it was registered. However,
numeric types have additional parameters which are extracted from the
actual SQL string of the type during lookup, and can have their behavior
change based on the result.

We simply need to use the block form of registration, and look up the
subtype lazily instead.

Fixes #17935

Fix grammar in Rakefile markup [ci skip]

Use latest web-console when using --dev or --edge

Fixes:

http://intertwingly.net/projects/AWDwR4/checkdepot-215/makedepot.log

remove unused `#generalized_table` and `#optional_parts`

This method was copied from journey at https://github.com/rails/rails/commit/56fee39c392788314c44a575b3fd66e16a50c8b5#diff-2cfaf53c860732fea8689d6f2002594bR78.
`grep -nr 'optional_parts' .`

This method wass copied from journey at https://github.com/rails/rails/commit/56fee39c392788314c44a575b3fd66e16a50c8b5#diff-d89de8881fc4b9f10cb3e4fc7b2463f3R53. However it looks the method was unused in journey at those point as well.

GlobalID objects are logged by their URI, not #inspect on the object, to prevent logging private data

Fix typo in "Hello World" template in German

Remove deprecated behavior allowing nested arrays as query values

Active Record defines `attribute_method_suffix :?`. That suffix will
match any predicate method when the lookup occurs in Active Model. This
will make it incorrectly decide that `id_changed?` should not exist,
because it attempts to determine if the attribute `id_changed` is
present, rather than `id` with the `_changed?` suffix. Instead, we will
look for any correct match.

Remove environment dependency for db:schema:load

All of the behavior :environment was giving (that db:schema:load needed)
was provided as well with :load_config.

This will address an issue introduced in
https://github.com/rails/rails/pull/15394. The fact that db:schema:load
now drops and creates the database causes the Octopus gem to have [an
issue](https://github.com/tchandy/octopus/issues/273) during the drop
step for the test database (which wasn't happening in db:schema:load
before). The error looks like:

    ActiveRecord::StatementInvalid: PG::ObjectInUse: ERROR:  cannot drop the currently open database
    : DROP DATABASE IF EXISTS "app_test"

Because of the timing, this issue is present in master, 4-2-*, and
4.1.8.

A note to forlorn developers who might see this: "Additionally" in a
commit message means you should have a separate commit, with a separate
justification for changes. Small commits with big messages are your
friends.

Deprecate `Class` handler in `PredicateBuilder`

Don't remove mailer layouts files

Fix Sidekiq ActiveJob integration setup

Conflicts:
	activejob/test/support/integration/adapters/sidekiq.rb

Users should pass strings to queries instead of classes

allow 'all' for :domain option in addition to :all

Add documentation to six AS::TimeWithZone methods [ci skip]

Fix MessageVerifier's #verified in CHANGELOG