Removed unused deprecation requires.

Added missing CHANGELOG from PR #11279 [ci skip]

Removed deprecated threadsafe! from Rails Config

Fixed test broken by local_constant_names 

depreciation removed

Deprecation removed

core extensions (`core_ext/string/encoding`).

in favor of `Module#local_constants`

Remove deprecated `ActiveRecord::Generators::ActiveModel#update_attribute`

    favor of `ActiveRecord::Generators::ActiveModel#update`

Thanks @egilburg.

Grammar fix debugging rails applications [ci skip]

Add patch level to Ruby version information

Given the recent security related patches to ruby and rails it is more
important than ever to know what patch level you are running.

Remove deprecated `Time` methods

    and `Time#local_time` in favour of `Time#utc` and `Time#local`

Remove deprecated `ActiveRecord::Fixtures.find_table_name` 

Remove deprecated `ActiveRecord::Fixtures.find_table_name` in favour of `ActiveRecord::Fixtures.default_fixture_model_name`.

according to http://guides.rubyonrails.org/api_documentation_guidelines.html#english

Removed deprecated method `columns_for_remove`

Improved grammar and replaced 'dbs' slang with 'databases'

If you're using it to compare hashes for the purpose of testing,
please use MiniTest's assert_equal instead.

Use symbols instead of strings in ActiveSupport::Concern

Making the rake file for tests easier to read.

Remove deprecated SchemaStatements#distinct