Changes:
- Added change log detection logic to container update feature. Since there isn't an official standard for how change logs are published in Docker images it uses a combination of OCI labels and fuzzy matching to try to determine the URL for the change log. Should work for about 70-80% of containers - issue #4
- Fix for displaying manifest digest instead of image digest - issue #5
- Bulk operation UI/UX fix
- Reworked migration system to be more robust and future-proof
- Added code to prevent DockMon from trying to update itself (which would've broken DockMon!)
- Since DockMon can't be updated by itself, added a feature to display a banner when a new version of DockMon is available