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.
Eliminate `JSON.{parse,load,generate,dump}` and `def to_json`

JSON.{dump,generate} offered by the JSON gem is not compatiable with
Rails at the moment and can cause a lot of subtle bugs when passed
certain data structures. This changed all direct usage of the JSON gem
in internal Rails code to always go through AS::JSON.{decode,encode}.

We also shouldn't be implementing `to_json` most of the time, and
these occurances are replaced with an equivilent `as_json`
implementation to avoid problems down the road.

See [1] for all the juicy details.

[1]: intridea/multi_json#138 (comment)
refine usage docs of `store` in combination with `hstore` and `json`.

refs #11561 #12700
Update Rails initialization guide to explain how bin/rails is executed