Updated 3.2.x link [ci skip]
Update I18n guide to note the additional features of the `translate` view helper
Update 3_2_release_notes.md

Code style adherence
Fixes typo
Update 4_0_release_notes.md

Code Highlighted
Update workaround for "Outside the Scope of Strong Parameters" 

The previous example of how to permit a hash of unknown keys used .tap, but had the side effect of logging an "Unpermitted parameters" message despite being a successful workaround. The proposed workaround is ever so slightly better, imo, because it won't result in an "Unpermitted parameters" message being logged.
warning about saving models with dirty attributes

See #8328
Fix undefined method error for NilClass

Add .try to prevent undefined method error for NilClass.
Fixed URL link to rendered_component plugin [ci skip]
rephrase the overriding views part about the view path

See rails/rails#12608
fix typo introduced when searching in markdown document with vim
guides/rails_on_rack: Fix formatting of _Internal Middleware Stack_ section
Hstore and JSON fields are not supported with store

The use of `store` on Hstore fields (for instance) is not needed
because serialization aimed to interact with Ruby objects and not
with provided field types
exists? is deprecated in ruby trunk [ci skip]

see here 4d4ff531b8807ee88a3fc46875c7e76f613956fb
Add test for ActiveRecord::Relation YAML serialization, for #5303 issue
Fixed code syntax for config.ru [ci skip]
Improve Errors when Controller Name or Action isn't specfied

These errors occur when, there routes are wrongly defined.

example, the following line would cause a missing :action error

    root "welcomeindex"

Mostly beginners are expected to hit these errors, so lets improve the error message a bit to make their learning experience bit better.
Don't swallow exceptions in transctional statements

The MySQL connection adapater swallows all StandardError exceptions,
which includes Mysql::Error and Mysql2::Error. The comment in the
exception clause claims errors thrown here indicate that transactions
aren't supported by the server but that isn't necessarily true. It's
possible the MySQL server has gone away and swallowing a failed commit
may let the application return a successful response when the data has
not been saved. Also, replication libraries like Galera require that the
application handle exceptions thrown at BEGIN/COMMIT.

I'm unable to determine what version of MySQL threw an exception for
transactional statements. I tried as far back as 3.23.49 with InnoDB
disabled but BEGIN & COMMIT statements do not throw an error. If there's
a real case for this logic to continue, we could instead push this
behavior into a configuration setting.

The exception swallowing has been there since the beginning:
db045dbbf60b53dbe013ef25554fd013baf88134
Fixed Object#as_json and Struct#as_json with options
These methods now takes the same options as Hash#as_json, for example:

    struct = Struct.new(:foo, :bar).new
    struct.foo = "hello"
    struct.bar = "world"
    json = struct.as_json(only: [:foo]) # => {foo: "hello"}

This is extracted from PR #11728 from @sergiocampama, see also the
discussion in #11460.
Merge pull request #12782 from chancancode/fix_object_and_struct_as_json

Fixed Object#as_json and Struct#as_json with options