Added a debug toolbar panel for MongoDB
I started to translate "guide-uz".
merge with upstream
Dynamic naming added to `DbPanel`
`MongoDbPanel` addition mentioned at CHANGELOG.md and README.md
Translate started

to be continued
update

update translate
update

update
`DbPanel` summary view fixed
Added polish guide
fix incorrect file status.
Update User.php

delete spaces
Added issue stats

- https://github.com/blog/1892-third-annual-data-challenge-winners
- http://issuestats.com/github/yiisoft/yii2
Merge pull request #5140 from gegebao/patch-1

[ci skip] Update User.php
Better date parsing and formatting including 32 bit support

Enhances `normalizeDateTimeValue` to return a DateTime object instead of a converted double value, that fails. The DateTime object input is supported by 32 bit, 64 bit, as well as the `IntlDateFormatter` to format all years. (including fixing of the Y2K38 bug). Fixes issue in #4989.

close #5000
format timestamps with invalid date input

fixes #4989
removed support for unlinkAll() from elasticsearch

feature is not reliable

fixes #5136
Fixes #5143: yii\bootstrap\ActiveField::label() should not encode label if it is explicitly specified. [skip ci]
reword/structure of the i18n and formatter guide
Update rest-rate-limiting.md

Чуть улучшил ясность написанного.