* 'master' of github.com:yiisoft/yii2:
  added more tests.

fixes #2184

fix the _only_ option in calls to FileHelper::findFiles()

Doc typo

Small typo in console-migrate.md

issue #2093

Fixes #1897

- Gii diff markup is now copy paste friendly
- Removed StringHelper::diff()
- Moved phpspec/php-diff dependency from yiisoft/yii2 to yiisoft/yii2-gii

Merge branch '2048-improve-messages-config-exceptions' of github.com:nineinchnick/yii2 into nineinchnick-2048-improve-messages-config-exceptions

Conflicts:
	framework/messages/config.php

Merge branch 'request-params-refactoring' of github.com:cebe/yii2 into cebe-request-params-refactoring

Conflicts:
	framework/CHANGELOG.md

fix

Allow writing widgets using return instead of echo in the run method to make it consistent with controller

Conflicts:
	framework/CHANGELOG.md

Codeception ext docs fix