Documentation Tweaks

• Emphasize that k3os.dns_nameservers and k3os.ntp_servers are fallback values. #347
• Add hetzner to supported data-sources. #355
  Also, adjust the data-sources documentation to indicate that datasources are tried in order until one returns some actual data, then processing stops.
• Note in the "Remastering ISO" section that some installations of grub2 grub-mkrescue drop files in ${ISO}/boot/grub2 #364
• Better Documentation for k3os.k3s_args in the README #373

Features and Enhancements

• Bump Alpine Base 3.11 #332
• Bump LTS/HWE Kernel 5.0.0-37.40-generic #350
  See https://usn.ubuntu.com/4209-1/ for relevant security fixes
• Bump K3S v1.17.2+k3s1 #362
• Kubernetes-Native Upgrades #348 , #353, #369
  See https://github.com/rancher/system-upgrade-controller
• Support TFTP and FTP URLS During Install for config_url and iso_url #352
• Support Hetzner Data Source #355
• Support UDEV #363, #371

Bug Fixes

• honor k3os.install.power_off when k3os.mode=install #143
• reboot on takeover install #228
• set reasonable system-wide limits and sysctls since we're running containers here #343
  Additionally, do linuxkit-style early hostname setting (as before v0.8.0)
• fix missing /etc/ssl/cert.pem expected by some busybox tooling (namely wget) #346

Deprecations

• deprecate k3os-upgrade-* scripts in favor of upgrade controller #369
  These are stillon system but they have been moved to /usr/share/rancher/k3os/scripts