added carousel widget
Merge remote-tracking branch 'upstream/master' into 331-bootstrap-carousel

* upstream/master:
  A little yii\bootstrap classes refactoring
refactored and apply suggested changes
Merge branch 'upstream' into 331-bootstrap-carousel

* upstream: (26 commits)
  Bootstrap widget comment typo fix
  Bugfix
  clientOptions and clientEvents
  yii\bootstrap\* another refactioring
  Better naming. Additional newline. Doctype tiny fix.
  MSSQL AR tests.
  MSSQL initial query builder.
  Refinements to MSSQL driver classes.
  jui.effect and jui.position dependencies
  Fixes #145. Reusable cache dependencies.
  jui.widget dependency
  Theme dependencies
  Datepicker language assets dependencies
  JQuery UI bundle assets config
  JQuery UI bundle assets
  Do comments at "yii\console\controllers\AssetController::saveTargets()" has been adjusted.
  "yii\console\controllers\AssetController::getAssetManager()" has been updated enforcing 'basePath' and 'baseUrl' config parameters.
  E_NOTICE at "yii\console\controllers\AssetController::loadBundleDependency()" has been fixed.
  Method "yii\console\controllers\AssetController::loadBundleDependency()" has been improved allowing dection of the circular dependency.
  Unit test for "yii\console\controllers\AssetController" has been adjusted.
  ...
some other fixes