Backup and restore wp-config.php as wp core multisite-install writes to it

[dnaber-de]

Provide a dynamic backup of wp-config.php for Wp\WpCliCore::multisiteInstall() and Wp\WpCliCore::multisiteConvert() as WP-CLI writes the multisite constants to the end of the file. This can break setups like those created with https://github.com/wecodemore/wpstarter

If the tools should automatically deal with config files, this should be abstracted in a separate API to give the user full control over it.