Merge pull request #750 from lucianobaraglia/master

Login url fix when called from a module [skip ci]
Refactored redirect() methods.
Merge branch 'master' of github.com:yiisoft/yii2
Reverted the change to User::loginUrl.
Added Controller::goHome().
Added login hint.
Fixed Menu active item check.
Fixed bootstrap Modal upgrade.
css fix.
fixes #736
code style fixes
fixed phpdoc
fixed User class namespace in phpdoc
removed unused import
bug fix.
Merge branch 'master' of github.com:yiisoft/yii2
Added more guide sections
Fixes #753: fixed sorting issue of ActiveDataProvider
Reorganized application template docs structure
basic application usage guide