KeyError exception when running execute()

[marcinkuzminski]

HI, when the script fails in pararell mode and i use execute to run several tasks i get this traceback:

Traceback (most recent call last):
  File "harmony/utils/bootstrap.py", line 149, in <module>
    user='ubuntu', password='qweqwe')
  File "harmony/utils/bootstrap.py", line 75, in bootstrap_machine
    execute(_worker, hosts=target_hosts)
  File "...python2.7/site-packages/fabric/tasks.py", line 323, in execute
    if isinstance(d['results'], BaseException):
KeyError: 'results'

Not sure how results is missing, but replacing that with d.get('results') fixes the issue.

[bitprophet]

This is an edge case in the parallel error handling where we're trying to avoid raising SystemExit errors twice, looks like we're not correctly adding it to the result data structure. Should be easily fixed.