replace locale with a language

The locale makes the tests fail.
Merge pull request #340 from greg0ire/fix_unit_tests

replace locale with a language
Added datepicker
Merge pull request #341 from Bladrak/datepicker

Added datepicker
Fixed locale in case of 404 error
Merge pull request #342 from mremi/fix-locale

Fixed locale in case of 404 error
fix unit tests
Merge pull request #344 from greg0ire/fix_unit_tests

fix unit tests
Merge remote-tracking branch 'sonata-project/master'