0.18.0

This release writes a lighthouse configuration file straight to a swarm.

New features

• Lighthouse configuration files for a swarm — swarm lh write and
  swarm lh check take a YAML file with -i/--input, as lh config write -i
  and lh config check -i do for one Crazyflie. The file is used instead of
  the stored configuration the swarm names, for example one from
  lh config read or the Crazyflie client. write skips the Crazyflies that
  already have it, as before. See
  docs/swarm.md.
  (#42)

  $ cfcli swarm lh write -i my_setup.yaml
  Lighthouse config from my_setup.yaml: base stations 4, 5, 6, 7
  CF-05: written and stored in flash
  CF-06: up to date
  

Improvements

• swarm lh loads the configuration first — a missing or broken file, or
  an unknown stored configuration, fails at once, before any Crazyradio is
  opened.
• swarm lh check suggests the right write — when Crazyflies differ, the
  swarm lh write it suggests includes the --config or -i that was given.
  It used to suggest plain swarm lh write, which writes the configuration
  the swarm names.