rkt 0.8.0-rc1 includes support for running containers under an LKVM hypervisor
and experimental user namespace support.

Full changelog:

• Documentation improvements
• Better integration with systemd:
  • journalctl -M
  • machinectl {reboot,poweroff}
• Update stage1's systemd to v222
• Add more functional tests
• Build system improvements
• Fix bugs with garbage-collection
• LKVM stage1 support with network and volumes
• Smarter image discovery: ETag and Cache-Control support
• Add CNI DHCP plugin
• Support systemd socket activation
• Backup CAS database when migrating
• Improve error messages
• Add the ability to override ACI exec
• Optimize rkt startup times when a stage1 is present in the store
• Trust keys fetched via TLS by default
• Add the ability to garbage-collect a specific pod
• Add experimental user namespace support
• Bugfixes