Comment 9 for bug 1687712

I recommend to back this change out and re-approach. 2 major things we found during testing

1) While this solution fixes the example given in the docs and the bug description, another error is hit as seen in comment #7 and comment #8. This needs debugging.

2) no protection against an array being specified originally. I.e., if someone had a config like this they are now broken:

#cloud-config
 fs_setup:
     - special:
       cmd: [ "mkfs", "-t" ... ]

The commit to back out appears to be 4f0f171c29bb9abb5cbb6f9adbe68015089aeed9