fixes bad json passed to create-stack call
fixes bad json passed to create-stack call

[#108585160](https://www.pivotaltracker.com/story/show/108585160)

Signed-off-by: Jonathan Barnes <bc7add126c2dbb8382bf1c28ac262b9363a32706@pivotal.io>

pivotal-golang/s3cli,pivotal-golang/s3cli,pivotal-golang/s3cli,pivotal-golang/s3cli