Merge pull request #20 from gregorybesson/master

Master
move entities from playground translate
remove useless route
add test for playground core
move flag
Merge pull request #21 from thomaroger/troger-move-entities

Move Entities from playground Translate
add cookie for locale
Merge pull request #22 from thomaroger/troger-change-locale-core

Update locale from cookie if exist
Merge pull request #23 from gregorybesson/develop

Locale management integrated into Core