Release v0.15.0

• Kill children properly (#601)

• Change name of Run binding for actions (#602)

• Add running commands to layouts (#600)

  POSSIBLE BREAKING CHANGE for custom layouts:
  Plugins are under the run category now, that means:

  plugin: status-bar
  

  is now:

  run:
      plugin: status-bar
  

• Add on_force_close config option (#609)