Added missing closing bracket for markdown url in guides [ci skip]

Moved README into action_view [ci skip]

This reverts commit 1468a4b8.

Refactor Date, Time, DateTime timezone methods

Similar implementations of #in_time_zone exists for Date, Time and DateTime so
method is extracted into its own module. Also some logic is extracted into
private method.

Remove duplication from date_time calculations

Change from `map` => `map!` and `collect!` to save creation of extra array

Methods: :past? and :future? are already defined identically
in date_and_time/calculations.rb which is included in Date.
Because DateTime is a subclass of Date, it can call them.

Remove $VERBOSE = nil from tasks.rb

Refactor `ArrayParser`

Make test order independent

Improve documentation for controller how to get included helpers

Closes #11671

Add retry to `gem install bundler` for Travis

This adds the retry behaviour used for other commands to the bundler installation.

postgresql test if randomly executed then executes "SHOW max_identifier_length". Hence
the need to ignore certain predefined sqls that deal with system calls.

AV::Digestor thread safety fixes

This fixes potential thread safety issues introduced in 09f6fe1c. The problem
with the original code was that the "recursion-stopping" `nil` values could
be seen by other threads.

Remove cow => kine from default inflections but leave the test case
in place to prevent regression of the [old Trac ticket 4929][1].

[1]: http://web.archive.org/web/20090314050915/http://dev.rubyonrails.org/ticket/4929

Conflicts:
	activerecord/CHANGELOG.md

Add ability to specify how a class is converted to Arel predicate when passed to where

order on the old ones

The previous behavior added a major backward incompatibility since it
impossible to have a upgrade path without major changes on the
application code.

We are taking the most conservative path to be consistent with the idea
of having a smoother upgrade on Rails 4.

We are reverting the behavior for what was in Rails 3.x and,
if needed, we will implement a new API to prepend the order clauses in
Rails 4.1.

Update of 'The Asset Pipeline' guide for Rails 4.

Added Time#middle_of_day method