Merge branch 'split/core' of https://github.com/contao/core into hotf…
…ix/4.3.6 # Conflicts: # src/Resources/contao/classes/DataContainer.php # src/Resources/contao/classes/Versions.php # src/Resources/contao/controllers/BackendInstall.php # src/Resources/contao/controllers/FrontendIndex.php # src/Resources/contao/dca/tl_files.php # src/Resources/contao/forms/FormSelectMenu.php # src/Resources/contao/library/Contao/Automator.php # src/Resources/contao/library/Contao/Controller.php # src/Resources/contao/library/Contao/System.php # src/Resources/contao/library/Contao/Template.php # src/Resources/contao/widgets/SelectMenu.php