* upstream: (35 commits)
  Fixes #1691: added “viewport” meta tag to layout views.
  Fixed the issue that query cache returns the same data for the same SQL but different query methods
  moved section
  subsection added
  typo [skip ci]
  docs about response
  Fixes #1586: `QueryBuilder::buildLikeCondition()` will now escape special characters and use percentage characters by default
  docs improved
  csrf docs added
  Fixes #1685: UrlManager::showScriptName should be set true for tests.
  Fixes #1688: ActiveForm is creating duplicated messages in error summary
  change back the visibility of findTableNames to protected.
  Typo fix.
  Fixes #1681: Added support for automatically adjusting the "for" attribute of label generated by `ActiveField::label()`
  Simplified tests.
  Fixes #1631: Charset is now explicitly set to UTF-8 when serving JSON
  Fixed typo
  added html layout for mail component in basic app
  CS fixes.
  Merge branch 'debug_module_improvements' of github.com:Ragazzo/yii2 into Ragazzo-debug_module_improvements
  ...

docs about response

Fixes #1586: `QueryBuilder::buildLikeCondition()` will now escape special characters and use percentage characters by default

csrf docs added

Fixes #1681: Added support for automatically adjusting the "for" attribute of label generated by `ActiveField::label()`

mail component in basic app

Merge branch 'debug_module_improvements' of github.com:Ragazzo/yii2 into Ragazzo-debug_module_improvements

Conflicts:
	extensions/yii/debug/panels/DbPanel.php

* origin/master:

Updated git-workflow.md to remove a false link

Refactored tests.

Replaced link to gitref.org to try.github.com as gitref.org is down.

enhance Inflector  helper with ascii function

* upstream:
  Fixed CSRF token masking issue.
  improved error message of calling invalid scope method.
  Fixed repo URL
  Fixes #1650: Added Connection::pdoClass.
  code style fix.
  added changelog
  codestyle fix
  improved checkIntegrity method
  Modified extension guidlines
  fix sphinx command signature
  fixed bug with forgotten param, fixed behavior for one table integrity
  fixed sequence reset
  added postgresql features to reset seq/check integrity