Release v0.5.0

- Require DNF v4+ and Leapp framework v0.5.0
- Improved handling of RPM transaction using own DNF plugin and PES
  data
- Models have been refactored to use new format supported by framework
- Handle transaction preparation when release is set through RHSM
- Fix failing overlayfs unmounting
- Reduce the IPUWorkflo workflow
- Include all required directories inside RPMs
- Handle repositories using metalink and mirrorlist
- Handle better installation of local RPMs
- Move system dependencies into the RPM metapackage
- Satisfy leapp and leapp-repository RPM dependencies during the
  upgrade

Release v0.4.0

• change hierarchy of repositories
• scan RHEL system for custom and 3rd-party packages
• improve error messages