Following up T177239
There's various .inc files that shouldn't be in maintenance... For example, someone unfamiliar with mediawiki might try and run backup.inc and wonder why it's not creating a backup.
Flow, for example, subclasses BackupDumper to make FlowDumpBackup, but also has a superfluous line of require_once $maintPath . '/backup.inc'; which isn't needed because the base class is in the MW autoloader
Targets for moving include.... 7zip.inc, backup.inc, backupPrefetch.inc