Release bolt 0.4 'The Race Is Over'

New features:

  • auto import of devices authorized during boot !90
  • allow enrolling of already authorized devices, i.e. importing of devices !86
  • label new devices and detect duplicates !91

Be more robust:

  • Handle NULL errors in logging code better !89
  • Properly handle empty device database entries !87
  • Better authentication errors and logging !85
  • More tests

Internal changes:

  • Make sure we don't miss device status changes !82
  • Rework property change notification dispatching !83