System requirements:
- User uploads 
$wgUploadDirectoryare stored offsite - Non-Docker MediaWiki with normal setup
 - Composor installed (Can be installed automatically during updating)
 
Goals:
- Update MediaWiki with nearly zero downtime
 - Download and install latest tagged MediaWiki from tarball package
 - Update extensions and skins from latest git tagged branch
 - Install extension-specific dependencies during updating