Fixes #1326: The `visible` setting for `DetailView` doesn't work as expected
fixed formatting
Persian (Farsi) Message Translations (fa-IR)
resolve a little bug in arabic translation file
Merge pull request #1938 from NabiKAZ/patch-1

resolve a little bug in arabic translation file
Some code style fixes [skip ci]
Merge pull request #1939 from NabiKAZ/fa_ir-translate-messages

Persian (Farsi) Message Translations (fa-IR)
Ukrainian translations
Merge pull request #1941 from yiiframework-com-ua/uk_translate

Ukrainian translations
Merge pull request #1940 from lucianobaraglia/some-cs-fixes

Some code style fixes [skip ci]
Fixes #1921: Grid view ActionColumn now allow to name buttons like `{controller/action}`
Migration command show correct directory path while it not exist
Merge pull request #1942 from creocoder/migrate-command-fix

Migration command show correct directory path while it not exist
ModelSerializer WIP
Fixed typo in Russian messages
Fixed typo in Russian translation
Changed extensions's guide section about namespaces once again
fixed typo
MongoDB Session class added.
MongoDB Cache class added as draft.