v0.3.0

Added

• The node applies an upgrade the hub asks for, running the package manager and restarting onto the
  new build unattended. (#161)

Fixed

• Connecting a node from the web app works: every hub probe runs as this node. (#163)
• dahrk start --token <new> restarts the node so a re-enrolment takes effect, and is refused while a
  stage is in flight. (#163)
• A parked node that finds a working token caches the token the hub accepted. (#163)
• A running node checks for a new release on the interval it reports. (#161)
• dahrk status reserves ✔ up to date for an answer from the current check interval, and reports an
  older one with its age. (#161)
• A failed update check is recorded, and the daemon logs the outcome of every check. (#161)