5.0.0-risalt

Implement an enhanced checksum framework.
Implement new resource (disk size).
Implement a negative match database.
Redo most of the TheGamesDB scraper.
Fix OpenRetro scraper.
Refactoring, correct C++ style and many fixes and small enhancements.

Full Changelog: https://github.com/risalt/skyscraper/commits/5.0.0-risalt