keep version numbers in their own files for faster reading

apps/admin_dependencies_chk/appinfo/info.xml

apps/admin_dependencies_chk/appinfo/version

apps/admin_migrate/appinfo/info.xml

apps/admin_migrate/appinfo/version

apps/bookmarks/appinfo/info.xml

apps/bookmarks/appinfo/version

apps/calendar/appinfo/info.xml

apps/calendar/appinfo/version

apps/contacts/appinfo/info.xml

apps/contacts/appinfo/version

apps/external/appinfo/info.xml

apps/external/appinfo/version

apps/files_archive/appinfo/info.xml

apps/files_archive/appinfo/version

apps/files_encryption/appinfo/info.xml

apps/files_encryption/appinfo/version

apps/files_external/appinfo/info.xml

apps/files_external/appinfo/version

apps/files_imageviewer/appinfo/info.xml

apps/files_imageviewer/appinfo/version