time.to_date conversion happens considering leap years
so a conversion of "Day.new({'day(1i)'=>'1', 'day(2i)'=>'1', 'day(3i)'=>'1'})" results in saving the date as Mon, 03 Jan 0001
which might seem weird on the user level, hence falling back to parsing on string level resolves this data mismatch
Fixes #28521

Previously table name qualified `*` is used in that case. If it is not
qualified with a table name, an ambiguous column name error will occur
when using JOINs.

Thanks to @Datasnuten for the suggestion.

Follow up of #31391

Update "Active Record Associations" guide [ci skip]

Fix Active Storage Overview guide [ci skip]

Currently, sidekiq integration test + Ruby 2.5.0-rc1 show exception as follows.

```
#<Thread:0x000000000670bec0@/home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/sidekiq-5.0.5/lib/sidekiq/util.rb:23 run> terminated with exception (report_on_exception is true):
/home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.1.7/lib/bootsnap/load_path_cache/core_ext/active_support.rb:53:in `block in load_missing_constant': uninitialized constant Sidekiq::CLI (NameError)
	from /home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.1.7/lib/bootsnap/load_path_cache/core_ext/active_support.rb:8:in `without_bootsnap_cache'
	from /home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.1.7/lib/bootsnap/load_path_cache/core_ext/active_support.rb:53:in `rescue in load_missing_constant'
	from /home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.1.7/lib/bootsnap/load_path_cache/core_ext/active_support.rb:42:in `load_missing_constant'
	from /home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/sidekiq-5.0.5/lib/sidekiq/launcher.rb:65:in `heartbeat'
	from /home/travis/build/rails/rails/vendor/bundle/ruby/2.5.0/gems/sidekiq-5.0.5/lib/sidekiq/launcher.rb:123:in `start_heartbeat'
```

https://travis-ci.org/rails/rails/jobs/317187279#L2152

The reason for this is that `Sidekiq::CLI` has not been loaded.
Sidekiq integration test launches a Sidekiq instance within
another Ruby process. In such a case, need to require 'sidekiq/cli'
in that launch code.

Ref: https://github.com/mperham/sidekiq/pull/3692#issuecomment-352032251

[ci skip] Use :amazon, not :s3, so that guides reflect the current code

The [template](https://github.com/rails/rails/blob/master/railties/lib/rails/generators/rails/app/templates/config/storage.yml.tt#L10)
that generates the `config/storage.yml` file has the Amazon S3 key specified as `:amazon`, not `:s3`.

The guides should reflect the nomenclature, given that every other service also
has the name of the company as the key (:google, :microsoft).

Modify test to correctly pass attributes hash

These are using `remove_column` directly, not used `t` in
`change_table`.

Like other Basics and Overview guides.

Fix in ASt guide [ci skip]

[ci skip] Inherit ActiveRecord::Base in example codes

Currently, generation of guide is an error in `5_2_release_notes.html`.

```
$ bunele exec rake guides:generate:html
Generating 5_2_release_notes.md as 5_2_release_notes.html
rails/guides/rails_guides/markdown.rb:44:in `dom_id': undefined method `[]' for nil:NilClass (NoMethodError)
	from rails/guides/rails_guides/markdown.rb:106:in `block (2 levels) in generate_structure'
```

It seems that it is an error because there are multiple
`active-storage` anchors.

Since Active Storage is a Major feature, it is unnecessary to show
CHANGELOGs, so remove from `Incompatibilities` section.

[ci skip] Add missing **DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.**

[ci skip] update link

[ci skip] Update guide index for active storage

`dump_schema_cache` fills `schema_cache` even if the test that modifies
the schema has properly cleared the schema cache.

Fixes #31463.

ActiveStorage Guide

`make_tmpname` was removed by https://github.com/ruby/ruby/commit/25d56ea7b7b52dc81af30c92a9a0e2d2dab6ff27.
In this case, we want a file name, not a `File`. So cannot use `Tempfile`.

Fixes #31458

Suppress `warning: BigDecimal.new is deprecated`

`BigDecimal.new` has been deprecated in BigDecimal 1.3.3
 which will be a default for Ruby 2.5.

Refer
https://github.com/ruby/bigdecimal/commit/533737338db915b00dc7168c3602e4b462b23503

* This commit has been made as follows:

```
cd rails
git grep -l BigDecimal.new | grep -v guides/source/5_0_release_notes.md | grep -v activesupport/test/xml_mini_test.rb | xargs sed -i -e "s/BigDecimal.new/BigDecimal/g"
```
- `activesupport/test/xml_mini_test.rb`
Editmanually to remove `.new` and `::`

- guides/source/5_0_release_notes.md
This is a Rails 5.0 release notes.

* The `DEFAULT_ERROR_HANDLER` constant in
  `ActiveSupport::Cache::RedisCacheStore` contained references
  to an undefined argument `e`, which is supposed to refer
  to the `exception` parameter.
* Update the default error handler proc to correctly reference
  the `exception` parameter.

Provide instant feedback when booting Rails

Suppress `warning: BigDecimal.new is deprecated` in Active Model