Breaking: #64143 - Language / Country Flag files moved

See forge#64143

Description

The static GIF file collection representing flags within typo3/gfx/flags/ has been removed. All PNG flag images from EXT:t3skin are moved from typo3/sysext/t3skin/images/flags/ to typo3/sysext/core/Resources/Public/Icons/flags/. The according stylesheets for the that flags-* icon files have been moved to EXT:core as well.

Impact

Any hard-coded reference on any of the files within typo3/gfx/flags/ and typo3/sysext/core/Resources/Public/Icons/flags/ will result in an error.

Changing the EXT:t3skin flags sprite now means changing the flags sprite of EXT:core.

Affected installations

Any installation using third-party extensions that access typo3/gfx/flags/ or typo3/sysext/t3skin/images/flags/ will fail.