Merge pull request #3114 from thiagotalma/patch-1

Update ActiveQuery.php
Added support for using sub-queries when building a DB query with `IN` condition
Fixes #3066: `yii\db\mssql\Schema::getTableSchema()` should return null when the table does not exist.
Added missing `ROWS` token when building limit/offset for MSSQL.
Added info about assets dir

http://www.yiiframework.com/forum/index.php/topic/53430-appasset-questions-getting-404-error-on-asset-files/page__gopid__246055#entry246055
Add yii\bootstrap\ActiveForm to the bootstrap guide
Merge pull request #3122 from mikehaertl/update-bootstrap-guide

Add yii\bootstrap\ActiveForm to the bootstrap guide
Fixes #3128: Fixed the bug that `defaultRoles` set in RBAC manager was not working as specified
Fixes #3127: added more doc [skip ci]
Fixes #3132: `yii\rbac\PhpManager` now supports more compact data file format
Fixes #3042: `yii\widgets\Pjax` should end application right after it finishes responding to a pjax request
Typecast model Id so that urls don't break when using MongoDB object Id's
Fixes #3121: `yii\base\Application::bootstrap` may fail to load some components if they are specified as class names
Supported adding a new response formatter without the need to reconfigure existing formatters
Correction of many errors code inspection.
Adjustments code according to the standards.
Adding missing PHPDoc comment.
Update error.php
Update error.php
Merge pull request #3138 from thiagotalma/inspections

Correction of many warnings code inspection.
Added `$user` as the first parameter of `yii\rbac\Rule::execute()`
Fixes test break.