For cf-promises, remove --parse-tree, replace with --policy-output-format

The changed flag does the same for now, but in order to get JSON output,
users must specify --policy-output-format=json

Currently 'none' and 'json' are the only valid values. 'none' is default
and will not print anything.
camelCase for --policy-output-format=json
Add namespace attribute to bodies and bundles in --policy-output-format=json
Merge pull request #341 from sigurdteigen/feature/policy-output-format

Feature/policy output format