Merge pull request #1962 from AlexEven/release

// wording
[-] BO : fixed bug #PSCSX-1832 - customer employee image in SAV
Merge branch 'release' of https://github.com/PrestaShop/PrestaShop into release
// Fixed John Doe secure key
[-] Core: don't cache the file_exists in Module::getInstanceByName
// AdminCustomersController.php: wording
// helpers/form/form.tpl: wording
//AdminEmployeesController.php: wording
// AdminThemesController.php: wording