Simplify usage of the orchestrator - config.json is the default config file

launch.sh

 #! /bin/sh -xe
 ./terraform apply -auto-approve "$@"
 ./terraform output -json > config.json
-./orchestrate.py -c config.json
+./orchestrate.py

orchestrate.py

@@ -12,7 +12,8 @@ DEFAULT_ACTIONS = ['files', 'ping', 'init', 'wait', 'deployment']
 
 parser = argparse.ArgumentParser(description='terraform cluster orchestrator')
 parser.add_argument('-c', '--config',
-                    help='Terraform output for using by orchestrator (default: -)', default='-')
+                    help='Terraform output for using by orchestrator (default: config.json)',
+                    default='config.json')
 parser.add_argument('actions', metavar='ACTIONS', nargs='*',
                     help='actions (default: %s)' % ' '.join(DEFAULT_ACTIONS),
                     default=DEFAULT_ACTIONS)