Sorts hapi json responses into known order to facilitate comparisons. GSON is the JSON library used, as it can be made to preserve insertion order (using a LinkedHashMap).

See also hapi-server/data-specification-schema#9, which describes the output needed:

• indents using 2-space indents
• json tag order should match the order which they are listed in the documentation
• each item of array has a separate line
• each tag of an object has a separate line
• each tag of an object does not have a space after the tag's name

See also https://github.com/hapi-server/data-specification/blob/master/hapi-3.1.0/HAPI-data-access-spec-3.1.0.md