Add Localization Files update

[matks]

We maintain repository https://github.com/PrestaShop/LocalizationFiles/

When the content of this repository is modified, the data must be copied into https://github.com/prestashop/prestashop as the Core data is a frozen copy of the data on https://github.com/PrestaShop/LocalizationFiles/ .

Before a new minor or major release is performed, it is necessary to make sure the data is up-to-date in https://github.com/prestashop/prestashop

[matks]

ping @sowbiba

[eternoendless]

Why not add it as a git submodule?

[matks]

Related to https://devdocs.prestashop.com/1.7/development/internationalization/localization-packs/