Allow multilevel dropdown.

moved magic methods

added total queries monitoring

Still needs an introduction and there are some questions to be
answered. Probably ought to demonstrate the code in an event handling
function.

renamed ActiveRecord::create() to populateRecord()

- refactored elasticsearch AR to make type and index available in
  instantiate(), issue #1313

fixes #2281

Convert database type to php

fixes #2276

I18n docs fix

see https://github.com/yiisoft/yii2/commit/0cfd41a21a8d89cc577590a253893542e60d43ce#commitcomment-5238567
issue #2233

fix kazakh translation